diff --git a/applications/test/DynamicList/Make/files b/applications/test/DynamicList/Make/files
index b496842582..76d78735b0 100644
--- a/applications/test/DynamicList/Make/files
+++ b/applications/test/DynamicList/Make/files
@@ -1,3 +1,3 @@
-Test-DynamicList.C
+Test-DynamicList.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-DynamicList
diff --git a/applications/test/DynamicList/Test-DynamicList.C b/applications/test/DynamicList/Test-DynamicList.cxx
similarity index 100%
rename from applications/test/DynamicList/Test-DynamicList.C
rename to applications/test/DynamicList/Test-DynamicList.cxx
diff --git a/applications/test/DynamicList2/Make/files b/applications/test/DynamicList2/Make/files
index 78b8198c6a..ceb29c7712 100644
--- a/applications/test/DynamicList2/Make/files
+++ b/applications/test/DynamicList2/Make/files
@@ -1,3 +1,3 @@
-Test-DynamicList2.C
+Test-DynamicList2.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-DynamicList2
diff --git a/applications/test/DynamicList2/Test-DynamicList2.C b/applications/test/DynamicList2/Test-DynamicList2.cxx
similarity index 87%
rename from applications/test/DynamicList2/Test-DynamicList2.C
rename to applications/test/DynamicList2/Test-DynamicList2.cxx
index e75e0d2986..ef47d26783 100644
--- a/applications/test/DynamicList2/Test-DynamicList2.C
+++ b/applications/test/DynamicList2/Test-DynamicList2.cxx
@@ -52,7 +52,8 @@ void printInfo
     if (showSize)
     {
         Info<< " size=\"" << list.size()
-            << "\" capacity=\"" << list.capacity() << "\"";
+            << "\" capacity=\"" << list.capacity() << "\""
+            << "\" min=\"" << SizeMin << "\"" ;
         if (list.cdata())
         {
             Info<< " ptr=\"" << name(list.cdata()) << "\"";
@@ -79,7 +80,8 @@ void printInfo
     if (showSize)
     {
         Info<< " size=\"" << list.size()
-            << "\" capacity=\"" << list.capacity() << "\"";
+            << "\" capacity=\"" << list.capacity() << "\""
+            << "\" min=\"" << SizeMin << "\"" ;
         if (list.cdata())
         {
             Info<< " ptr=\"" << name(list.cdata()) << "\"";
@@ -168,6 +170,22 @@ int main(int argc, char *argv[])
         printInfo("", list2);
     }
 
+    {
+        DynamicList<float, 32> list1(std::pair<label,label>(16,0));
+        list1 = -1;
+
+        Info<< "construct with specified size/capacity" << nl;
+        printInfo("", list1);
+    }
+
+    {
+        DynamicList<float, 32> list1(std::pair<label,label>(8,16));
+        list1 = -1;
+
+        Info<< "construct with specified size/capacity" << nl;
+        printInfo("", list1);
+    }
+
     Info<< "\nEnd\n";
 
     return 0;
diff --git a/applications/test/List3/Make/files b/applications/test/List3/Make/files
index 640cc113d7..93c443e14e 100644
--- a/applications/test/List3/Make/files
+++ b/applications/test/List3/Make/files
@@ -1,3 +1,3 @@
-Test-List3.C
+Test-List3.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-List3
diff --git a/applications/test/List3/Test-List3.C b/applications/test/List3/Test-List3.cxx
similarity index 100%
rename from applications/test/List3/Test-List3.C
rename to applications/test/List3/Test-List3.cxx
diff --git a/applications/test/PackedList1/Make/files b/applications/test/PackedList1/Make/files
index 76843f21f9..0b2b68d6ff 100644
--- a/applications/test/PackedList1/Make/files
+++ b/applications/test/PackedList1/Make/files
@@ -1,3 +1,3 @@
-Test-PackedList1.C
+Test-PackedList1.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-PackedList1
diff --git a/applications/test/PackedList1/Test-PackedList1.C b/applications/test/PackedList1/Test-PackedList1.cxx
similarity index 100%
rename from applications/test/PackedList1/Test-PackedList1.C
rename to applications/test/PackedList1/Test-PackedList1.cxx
diff --git a/applications/test/PackedList2/Make/files b/applications/test/PackedList2/Make/files
index ce31f2fa8d..7c20add1a5 100644
--- a/applications/test/PackedList2/Make/files
+++ b/applications/test/PackedList2/Make/files
@@ -1,3 +1,3 @@
-Test-PackedList2.C
+Test-PackedList2.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-PackedList2
diff --git a/applications/test/PackedList2/Test-PackedList2.C b/applications/test/PackedList2/Test-PackedList2.cxx
similarity index 100%
rename from applications/test/PackedList2/Test-PackedList2.C
rename to applications/test/PackedList2/Test-PackedList2.cxx
diff --git a/applications/test/UIndirectList/Make/files b/applications/test/UIndirectList/Make/files
index 8f70521989..9be6c13178 100644
--- a/applications/test/UIndirectList/Make/files
+++ b/applications/test/UIndirectList/Make/files
@@ -1,3 +1,3 @@
-Test-UIndirectList.C
+Test-UIndirectList.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-UIndirectList
diff --git a/applications/test/UIndirectList/Test-UIndirectList.C b/applications/test/UIndirectList/Test-UIndirectList.cxx
similarity index 100%
rename from applications/test/UIndirectList/Test-UIndirectList.C
rename to applications/test/UIndirectList/Test-UIndirectList.cxx
diff --git a/applications/test/bitSet2/Make/files b/applications/test/bitSet2/Make/files
index ff546fa179..e3ceca9e23 100644
--- a/applications/test/bitSet2/Make/files
+++ b/applications/test/bitSet2/Make/files
@@ -1,3 +1,3 @@
-Test-bitSet2.C
+Test-bitSet2.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-bitSet2
diff --git a/applications/test/bitSet2/Test-bitSet2.C b/applications/test/bitSet2/Test-bitSet2.cxx
similarity index 99%
rename from applications/test/bitSet2/Test-bitSet2.C
rename to applications/test/bitSet2/Test-bitSet2.cxx
index fb9bc746a1..8f9f5d487e 100644
--- a/applications/test/bitSet2/Test-bitSet2.C
+++ b/applications/test/bitSet2/Test-bitSet2.cxx
@@ -499,7 +499,7 @@ int main(int argc, char *argv[])
         Info<<"bitSet ";
         report(list4);
 
-        list4.shrink();
+        list4.shrink_to_fit();
         Info<<"shrunk ";
         report(list4);
 
diff --git a/src/OpenFOAM/containers/Bits/PackedList/PackedList.H b/src/OpenFOAM/containers/Bits/PackedList/PackedList.H
index 5bdbbceb6a..aa6c755962 100644
--- a/src/OpenFOAM/containers/Bits/PackedList/PackedList.H
+++ b/src/OpenFOAM/containers/Bits/PackedList/PackedList.H
@@ -406,7 +406,10 @@ public:
         inline void clearStorage();
 
         //- Shrink the allocated space to what is actually used.
-        inline void shrink();
+        inline void shrink_to_fit();
+
+        //- Alias for shrink_to_fit()
+        void shrink() { this->shrink_to_fit(); }
 
         //- Swap contents with argument
         inline void swap(PackedList<Width>& rhs);
diff --git a/src/OpenFOAM/containers/Bits/PackedList/PackedListI.H b/src/OpenFOAM/containers/Bits/PackedList/PackedListI.H
index 8bdd10ddcc..a8e7f93dd9 100644
--- a/src/OpenFOAM/containers/Bits/PackedList/PackedListI.H
+++ b/src/OpenFOAM/containers/Bits/PackedList/PackedListI.H
@@ -597,7 +597,7 @@ inline void Foam::PackedList<Width>::clearStorage()
 
 
 template<unsigned Width>
-inline void Foam::PackedList<Width>::shrink()
+inline void Foam::PackedList<Width>::shrink_to_fit()
 {
     // Any unneeded space allocated?
     const label nblocks = num_blocks(size());
diff --git a/src/OpenFOAM/containers/Lists/DynamicList/DynamicList.H b/src/OpenFOAM/containers/Lists/DynamicList/DynamicList.H
index 78385c9b5b..bf8768d9bc 100644
--- a/src/OpenFOAM/containers/Lists/DynamicList/DynamicList.H
+++ b/src/OpenFOAM/containers/Lists/DynamicList/DynamicList.H
@@ -120,6 +120,9 @@ public:
         //- Construct an empty list with given initial capacity
         inline explicit DynamicList(const label initialCapacity);
 
+        //- Construct with given size and capacity
+        inline explicit DynamicList(const std::pair<label,label>& sizing);
+
         //- Construct with given size and value for all elements.
         inline DynamicList(const label len, const T& val);
 
@@ -133,21 +136,21 @@ public:
         template<int AnySizeMin>
         inline DynamicList(const DynamicList<T, AnySizeMin>& lst);
 
-        //- Construct from UList. Size set to UList size.
+        //- Copy construct from UList. Size set to UList size.
         //  Also constructs from DynamicList with different sizing parameters.
         inline explicit DynamicList(const UList<T>& lst);
 
         //- Copy construct subset of list
         inline DynamicList(const UList<T>& list, const labelUList& indices);
 
-        //- Construct from a FixedList
+        //- Copy construct from a FixedList
         template<unsigned N>
         inline explicit DynamicList(const FixedList<T, N>& lst);
 
-        //- Construct from an initializer list. Size set to list size.
+        //- Copy construct from an initializer list. Size set to list size.
         inline explicit DynamicList(std::initializer_list<T> lst);
 
-        //- Construct from IndirectList. Size set to addressing size.
+        //- Copy construct from IndirectList. Size set to addressing size.
         template<class Addr>
         inline explicit DynamicList(const IndirectListBase<T, Addr>& lst);
 
@@ -200,7 +203,7 @@ public:
 
         //- Change the value for the list capacity directly (ADVANCED, UNSAFE)
         //- Does not perform any memory management or resizing.
-        inline void setCapacity_unsafe(const label len) noexcept;
+        void setCapacity_unsafe(const label len) noexcept { capacity_ = len; }
 
         //- Reserve allocation space for at least this size, allocating new
         //- space if required and \em retaining old content.
@@ -238,12 +241,6 @@ public:
         //  Otherwise all entries will be uninitialized.
         inline void resize_nocopy(const label len);
 
-        //- Same as resize()
-        void setSize(const label n) { this->resize(n); }
-
-        //- Same as resize()
-        void setSize(const label n, const T& val) { this->resize(n, val); }
-
         //- Clear the addressed list, i.e. set the size to zero.
         //  Allocated size does not change
         inline void clear() noexcept;
@@ -259,9 +256,6 @@ public:
         //  \note when empty() it will delete any allocated memory.
         inline void shrink_unsafe();
 
-        //- Calls shrink_to_fit() and returns a reference to the DynamicList.
-        inline DynamicList<T, SizeMin>& shrink();
-
 
     // Edit
 
@@ -304,7 +298,7 @@ public:
         template<class Addr>
         inline void push_back(const IndirectListBase<T, Addr>& lst);
 
-        //- Move append list
+        //- Move append another list to the end of this list
         inline void push_back(List<T>&& list);
 
         //- Move append list
@@ -355,10 +349,10 @@ public:
             //- Return non-const access to an element, resizing list if needed
             inline T& operator()(const label i);
 
-            //- Assignment of all addressed entries to the given value
+            //- Assign addressed entries to the given value
             inline void operator=(const T& val);
 
-            //- Assignment of all entries to zero
+            //- Assign addressed entries to zero
             inline void operator=(Foam::zero);
 
             //- Assignment to UList
@@ -418,6 +412,20 @@ public:
 
     // Housekeeping
 
+        //- Alias for resize()
+        void setSize(const label n) { this->resize(n); }
+
+        //- Alias for resize()
+        void setSize(const label n, const T& val) { this->resize(n, val); }
+
+        //- Calls shrink_to_fit() and returns a reference to the DynamicList.
+        //FOAM_DEPRECATED_FOR(2025-04, "shrink_to_fit()")
+        DynamicList<T, SizeMin>& shrink()
+        {
+            this->shrink_to_fit();
+            return *this;
+        }
+
         //- Copy append an element to the end of this list.
         //FOAM_DEPRECATED_FOR(2022-10, "push_back()")
         void append(const T& val) { this->push_back(val); }
diff --git a/src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H b/src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H
index a3c004cd8a..17e199242d 100644
--- a/src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H
+++ b/src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H
@@ -42,7 +42,7 @@ inline void Foam::DynamicList<T, SizeMin>::doAssignDynList
     if (capacity_ < len)
     {
         // Needs more space for the copy operation
-        List<T>::setAddressableSize(capacity_);  // Use entire space
+        List<T>::setAddressableSize(capacity_);
         List<T>::resize_nocopy(len);
         capacity_ = List<T>::size();
     }
@@ -68,23 +68,14 @@ inline void Foam::DynamicList<T, SizeMin>::doCapacity
     // Addressable length, possibly truncated by new capacity
     const label currLen = Foam::min(List<T>::size(), newCapacity);
 
-    // Corner case...
-    if (List<T>::size() == newCapacity)
-    {
-        // Adjust addressable size to trigger proper resizing.
-        // Using (old size+1) is safe since it does not affect the 'overlap'
-        // of old and new addressable regions, but incurs fewew copy
-        // operations than extending to use the current capacity would.
-        List<T>::setAddressableSize(currLen+1);
-    }
-
+    List<T>::setAddressableSize(capacity_);
     if (nocopy)
     {
         List<T>::resize_nocopy(newCapacity);
     }
     else
     {
-        List<T>::resize(newCapacity);
+        List<T>::resize_copy(currLen, newCapacity);
     }
 
     capacity_ = List<T>::size();
@@ -153,6 +144,19 @@ inline Foam::DynamicList<T, SizeMin>::DynamicList(const label initialCapacity)
 }
 
 
+template<class T, int SizeMin>
+inline Foam::DynamicList<T, SizeMin>::DynamicList
+(
+    const std::pair<label,label>& sizing
+)
+:
+    List<T>(std::max(sizing.first, sizing.second)),
+    capacity_(List<T>::size())
+{
+    List<T>::setAddressableSize(sizing.first);
+}
+
+
 template<class T, int SizeMin>
 inline Foam::DynamicList<T, SizeMin>::DynamicList
 (
@@ -326,16 +330,6 @@ inline void Foam::DynamicList<T, SizeMin>::setCapacity_nocopy
 }
 
 
-template<class T, int SizeMin>
-inline void Foam::DynamicList<T, SizeMin>::setCapacity_unsafe
-(
-    const label len
-) noexcept
-{
-    capacity_ = len;
-}
-
-
 template<class T, int SizeMin>
 inline void Foam::DynamicList<T, SizeMin>::reserve
 (
@@ -448,8 +442,7 @@ inline void Foam::DynamicList<T, SizeMin>::shrink_to_fit()
     const label currLen = List<T>::size();
     if (currLen < capacity_)
     {
-        // Adjust addressable size to trigger proper resizing
-        List<T>::setAddressableSize(currLen+1);
+        List<T>::setAddressableSize(capacity_);
         List<T>::resize(currLen);
         capacity_ = List<T>::size();
     }
@@ -468,15 +461,6 @@ inline void Foam::DynamicList<T, SizeMin>::shrink_unsafe()
 }
 
 
-template<class T, int SizeMin>
-inline Foam::DynamicList<T, SizeMin>&
-Foam::DynamicList<T, SizeMin>::shrink()
-{
-    this->shrink_to_fit();
-    return *this;
-}
-
-
 template<class T, int SizeMin>
 inline void
 Foam::DynamicList<T, SizeMin>::swap(List<T>& list)
@@ -608,7 +592,7 @@ inline void Foam::DynamicList<T, SizeMin>::push_back
     const UList<T>& list
 )
 {
-    if (this == &list)
+    if (FOAM_UNLIKELY(this == &list))
     {
         FatalErrorInFunction
             << "Attempted push_back to self"
@@ -662,8 +646,7 @@ inline void Foam::DynamicList<T, SizeMin>::push_back
 
     const label idx = this->size();
     const label n = list.size();
-
-    resize(list + n);
+    resize(idx + n);
 
     auto iter = this->begin(idx);
 
@@ -680,7 +663,7 @@ inline void Foam::DynamicList<T, SizeMin>::push_back
     List<T>&& list
 )
 {
-    if (this == &list)
+    if (FOAM_UNLIKELY(this == &list))
     {
         FatalErrorInFunction
             << "Attempted push_back to self"
diff --git a/src/OpenFOAM/containers/Lists/List/List.C b/src/OpenFOAM/containers/Lists/List/List.C
index bdf09f58c5..c9707ef29b 100644
--- a/src/OpenFOAM/containers/Lists/List/List.C
+++ b/src/OpenFOAM/containers/Lists/List/List.C
@@ -31,31 +31,34 @@ License
 #include "PtrList.H"
 #include "contiguous.H"
 
-// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
+// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
 
 template<class T>
-void Foam::List<T>::doResize(const label len)
+void Foam::List<T>::resize_copy(const label count, const label len)
 {
-    if (len == this->size_)
-    {
-        return;
-    }
+    // Only a limited number of internal size checks.
+    // Caller knows what they are doing.
 
-    if (len > 0)
+    if (FOAM_LIKELY(len > 0))
     {
         // With sign-check to avoid spurious -Walloc-size-larger-than
-        const label overlap = Foam::min(this->size_, len);
+        // const label oldLen = this->size_;
+        const label overlap = Foam::min(count, len);
+        // Extra safety, not currently necessary:
+        // const label overlap = Foam::min(Foam::min(count, oldLen), len);
+
+        T* old = this->v_;
 
         if (overlap > 0)
         {
             // Recover overlapping content when resizing
-            T* old = this->v_;
+
             this->size_ = len;
             this->v_ = new T[len];
 
             // Can dispatch with
-            // - std::execution::parallel_unsequenced_policy
-            // - std::execution::unsequenced_policy
+            // - std::execution::par_unseq
+            // - std::execution::unseq
             std::move(old, (old + overlap), this->v_);
 
             delete[] old;
@@ -63,7 +66,8 @@ void Foam::List<T>::doResize(const label len)
         else
         {
             // No overlapping content
-            delete[] this->v_;
+            delete[] old;
+
             this->size_ = len;
             this->v_ = new T[len];
         }
@@ -71,7 +75,7 @@ void Foam::List<T>::doResize(const label len)
     else
     {
         // Or only #ifdef FULLDEBUG
-        if (len < 0)
+        if (FOAM_UNLIKELY(len < 0))
         {
             FatalErrorInFunction
                 << "bad size " << len
@@ -91,14 +95,17 @@ Foam::List<T>::List(const label len)
 :
     UList<T>(nullptr, len)
 {
-    if (len < 0)
+    if (FOAM_UNLIKELY(len < 0))
     {
         FatalErrorInFunction
             << "bad size " << len
             << abort(FatalError);
     }
 
-    doAlloc();
+    if (len > 0)
+    {
+        doAlloc();
+    }
 }
 
 
@@ -107,14 +114,14 @@ Foam::List<T>::List(const label len, const T& val)
 :
     UList<T>(nullptr, len)
 {
-    if (len < 0)
+    if (FOAM_UNLIKELY(len < 0))
     {
         FatalErrorInFunction
             << "bad size " << len
             << abort(FatalError);
     }
 
-    if (len)
+    if (len > 0)
     {
         doAlloc();
         UList<T>::operator=(val);
@@ -127,14 +134,14 @@ Foam::List<T>::List(const label len, Foam::zero)
 :
     UList<T>(nullptr, len)
 {
-    if (len < 0)
+    if (FOAM_UNLIKELY(len < 0))
     {
         FatalErrorInFunction
             << "bad size " << len
             << abort(FatalError);
     }
 
-    if (len)
+    if (len > 0)
     {
         doAlloc();
         UList<T>::operator=(Foam::zero{});
@@ -206,10 +213,8 @@ Foam::List<T>::List(List<T>& list, bool reuse)
         this->v_ = list.v_;
         list.v_ = nullptr;
         list.size_ = 0;
-        return;
     }
-
-    if (this->size_)
+    else if (this->size_ > 0)
     {
         doAlloc();
         UList<T>::deepCopy(list);
@@ -316,7 +321,13 @@ template<class T>
 void Foam::List<T>::resize(const label len, const T& val)
 {
     const label oldLen = this->size_;
-    this->doResize(len);
+
+    if (oldLen == len)
+    {
+        return;
+    }
+
+    this->resize_copy(oldLen, len);
 
     // Fill trailing part with new values
     if (oldLen < this->size_)
diff --git a/src/OpenFOAM/containers/Lists/List/List.H b/src/OpenFOAM/containers/Lists/List/List.H
index 8f2d96a99f..5c9d7d1c8f 100644
--- a/src/OpenFOAM/containers/Lists/List/List.H
+++ b/src/OpenFOAM/containers/Lists/List/List.H
@@ -93,10 +93,6 @@ class List
         template<class ListType, class ListIndices>
         inline void copyList(const ListType& list, const ListIndices& indices);
 
-        //- Change allocation size of List, retaining old contents.
-        //  Backend for resize
-        void doResize(const label len);
-
         //- Construct given begin/end iterators and number of elements
         //  Since the size is provided, the end iterator is actually ignored.
         template<class InputIterator>
@@ -118,6 +114,16 @@ class List
         void setCapacity_nocopy(const label len) { resize_nocopy(len); }
 
 
+protected:
+
+    // Protected Member Functions
+
+        //- Low-level resizing (backend for resize).
+        //- Change allocation size of list, retaining the first count contents.
+        //  \note Only uses a limited number of internal checks.
+        void resize_copy(const label count, const label len);
+
+
 public:
 
     // Related types
diff --git a/src/OpenFOAM/containers/Lists/List/ListI.H b/src/OpenFOAM/containers/Lists/List/ListI.H
index bdb510f837..228df08392 100644
--- a/src/OpenFOAM/containers/Lists/List/ListI.H
+++ b/src/OpenFOAM/containers/Lists/List/ListI.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2017-2023 OpenCFD Ltd.
+    Copyright (C) 2017-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -102,7 +102,7 @@ inline Foam::List<T>::List
 :
     UList<T>(nullptr, len)
 {
-    if (this->size_)
+    if (len > 0)
     {
         doAlloc();
 
@@ -149,9 +149,9 @@ namespace Foam
 {
     // Template specialization for bool. Fills new entries with false
     template<>
-    inline void List<bool>::resize(const label newLen)
+    inline void List<bool>::resize(const label len)
     {
-        this->resize(newLen, false);
+        this->resize(len, false);
     }
 }
 
@@ -159,7 +159,10 @@ namespace Foam
 template<class T>
 inline void Foam::List<T>::resize(const label len)
 {
-    this->doResize(len);
+    if (this->size_ != len)
+    {
+        this->resize_copy(this->size_, len);
+    }
 }
 
 
@@ -269,7 +272,6 @@ inline void Foam::List<T>::push_back(const IndirectListBase<T, Addr>& list)
 
     const label idx = this->size();
     const label n = list.size();
-
     resize(idx + n);
 
     auto iter = this->begin(idx);
diff --git a/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynList.H b/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynList.H
index ee33bbef2d..f55ee7e022 100644
--- a/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynList.H
+++ b/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynList.H
@@ -76,9 +76,12 @@ public:
         //- Default construct
         inline constexpr PtrDynList() noexcept;
 
-        //- Construct with given capacity.
+        //- Construct with given initial capacity
         inline explicit PtrDynList(const label len);
 
+        //- Construct with given size and capacity
+        inline explicit PtrDynList(const std::pair<label,label>& sizing);
+
         //- Copy construct using 'clone()' method on each element
         inline PtrDynList(const PtrDynList<T, SizeMin>& list);
 
@@ -107,6 +110,10 @@ public:
         //- Size of the underlying storage.
         label capacity() const noexcept { return capacity_; }
 
+        //- Change the value for the list capacity directly (ADVANCED, UNSAFE)
+        //- Does not perform any memory management or resizing.
+        void setCapacity_unsafe(const label len) noexcept { capacity_ = len; }
+
         //- Reserve allocation space for at least this size.
         inline void reserve(const label len);
 
@@ -138,8 +145,8 @@ public:
         //  \note when empty() it will delete any allocated memory.
         inline void shrink_unsafe();
 
-        //- Calls shrink_to_fit()
-        void shrink() { shrink_to_fit(); }
+        //- Alias for shrink_to_fit()
+        void shrink() { this->shrink_to_fit(); }
 
 
     // Edit
diff --git a/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynListI.H b/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynListI.H
index fccedeccfb..79763cf398 100644
--- a/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynListI.H
+++ b/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynListI.H
@@ -49,6 +49,19 @@ inline Foam::PtrDynList<T, SizeMin>::PtrDynList(const label len)
 }
 
 
+template<class T, int SizeMin>
+inline Foam::PtrDynList<T, SizeMin>::PtrDynList
+(
+    const std::pair<label,label>& sizing
+)
+:
+    PtrList<T>(std::max(sizing.first, sizing.second)),
+    capacity_(PtrList<T>::size())
+{
+    PtrList<T>::setAddressableSize(sizing.first);
+}
+
+
 template<class T, int SizeMin>
 inline Foam::PtrDynList<T, SizeMin>::PtrDynList
 (
@@ -220,8 +233,7 @@ inline void Foam::PtrDynList<T, SizeMin>::shrink_to_fit()
     const label currLen = PtrList<T>::size();
     if (currLen < capacity_)
     {
-        // Adjust addressable size to trigger proper resizing
-        PtrList<T>::setAddressableSize(currLen+1);
+        PtrList<T>::setAddressableSize(capacity_);
         PtrList<T>::resize(currLen);
         capacity_ = PtrList<T>::size();
     }
diff --git a/src/OpenFOAM/containers/PtrLists/PtrList/PtrList.H b/src/OpenFOAM/containers/PtrLists/PtrList/PtrList.H
index 72c8389278..89e4a9688a 100644
--- a/src/OpenFOAM/containers/PtrLists/PtrList/PtrList.H
+++ b/src/OpenFOAM/containers/PtrLists/PtrList/PtrList.H
@@ -249,7 +249,7 @@ public:
         }
 
         //- Same as resize()
-        void setSize(const label newLen) { this->resize(newLen); }
+        void setSize(const label n) { this->resize(n); }
 
         //- Move append an element to the end of the list
         //FOAM_DEPRECATED_FOR(2022-10, "push_back()")
diff --git a/src/OpenFOAM/fields/Fields/DynamicField/DynamicField.H b/src/OpenFOAM/fields/Fields/DynamicField/DynamicField.H
index 5f73c83e11..7451c5ffde 100644
--- a/src/OpenFOAM/fields/Fields/DynamicField/DynamicField.H
+++ b/src/OpenFOAM/fields/Fields/DynamicField/DynamicField.H
@@ -29,6 +29,7 @@ Class
 
 Description
     Dynamically sized Field.
+    Similar to DynamicList, but inheriting from a Field instead of a List.
 
 SourceFiles
     DynamicFieldI.H
@@ -95,15 +96,6 @@ class DynamicField
 
 public:
 
-    // Static Member Functions
-
-        //- Return a null DynamicField (reference to a nullObject).
-        static const DynamicField<T, SizeMin>& null() noexcept
-        {
-            return NullObjectRef<DynamicField<T, SizeMin>>();
-        }
-
-
     // Constructors
 
         //- Default construct, an empty field without allocation.
@@ -112,11 +104,14 @@ public:
         //- Construct empty field with given initial capacity
         inline explicit DynamicField(const label initialCapacity);
 
+        //- Construct with given size and capacity
+        inline explicit DynamicField(const std::pair<label,label>& sizing);
+
         //- Construct given size and initial value
         inline DynamicField(const label len, const T& val);
 
         //- Construct given size and initial value of zero
-        inline DynamicField(const label len, const Foam::zero);
+        inline DynamicField(const label len, Foam::zero);
 
         //- Copy construct
         inline DynamicField(const DynamicField<T, SizeMin>& list);
@@ -222,7 +217,7 @@ public:
 
         //- Change the value for the list capacity directly (ADVANCED, UNSAFE)
         //- Does not perform any memory management or resizing.
-        inline void setCapacity_unsafe(const label len) noexcept;
+        void setCapacity_unsafe(const label len) noexcept { capacity_ = len; }
 
         //- Reserve allocation space for at least this size, allocating new
         //- space if required and \em retaining old content.
@@ -248,21 +243,18 @@ public:
         //  setting values (as per List usage).
         inline void resize(const label len);
 
-        //- Alter addressable size and fill new space with constant value
+        //- Alter addressable size and fill \em new entries with constant value
         inline void resize(const label len, const T& val);
 
+        //- Alter addressable size and set val for \em all addressed entries
+        inline void resize_fill(const label len, const T& val);
+
         //- Alter addressable list size, allocating new space if required
         //- \em without necessarily recovering old content.
         //  If no reallocation is required, the contents remain untouched.
         //  Otherwise all entries will be uninitialized.
         inline void resize_nocopy(const label len);
 
-        //- Alias for resize()
-        void setSize(const label n) { this->resize(n); }
-
-        //- Alias for resize()
-        void setSize(const label n, const T& val) { this->resize(n, val); }
-
         //- Clear the addressed list, i.e. set the size to zero.
         //  Allocated size does not change
         inline void clear() noexcept;
@@ -278,9 +270,6 @@ public:
         //  \note when empty() it will delete any allocated memory.
         inline void shrink_unsafe();
 
-        //- Calls shrink_to_fit() and returns a reference to the DynamicField.
-        inline DynamicField<T, SizeMin>& shrink();
-
 
     // Edit
 
@@ -289,11 +278,11 @@ public:
 
         //- Swap content, independent of sizing parameter
         template<int AnySizeMin>
-        inline void swap(DynamicField<T, AnySizeMin>& other);
+        inline void swap(DynamicField<T, AnySizeMin>& other) noexcept;
 
         //- Swap content with DynamicList, independent of sizing parameter
         template<int AnySizeMin>
-        inline void swap(DynamicList<T, AnySizeMin>& other);
+        inline void swap(DynamicList<T, AnySizeMin>& other) noexcept;
 
         //- Transfer the parameter contents into this
         inline void transfer(List<T>& list);
@@ -311,7 +300,7 @@ public:
         template<class... Args>
         inline T& emplace_back(Args&&... args);
 
-        //- Copy append an element at the end of the list
+        //- Copy append an element to the end of the list
         inline void push_back(const T& val);
 
         //- Move append an element
@@ -340,7 +329,7 @@ public:
         inline void operator=(const T& val);
 
         //- Assign addressed entries to zero
-        inline void operator=(const Foam::zero);
+        inline void operator=(Foam::zero);
 
         //- Copy assignment
         inline void operator=(const UList<T>& list);
@@ -392,6 +381,20 @@ public:
 
     // Housekeeping
 
+        //- Alias for resize()
+        void setSize(const label n) { this->resize(n); }
+
+        //- Alias for resize()
+        void setSize(const label n, const T& val) { this->resize(n, val); }
+
+        //- Calls shrink_to_fit() and returns a reference to the DynamicField.
+        //FOAM_DEPRECATED_FOR(2025-04, "shrink_to_fit()")
+        DynamicField<T, SizeMin>& shrink()
+        {
+            this->shrink_to_fit();
+            return *this;
+        }
+
         //- Append an element at the end of the list
         //FOAM_DEPRECATED_FOR(2022-10, "push_back()")
         void append(const T& val) { this->push_back(val); }
diff --git a/src/OpenFOAM/fields/Fields/DynamicField/DynamicFieldI.H b/src/OpenFOAM/fields/Fields/DynamicField/DynamicFieldI.H
index 18012d91f2..1b5b6fd69d 100644
--- a/src/OpenFOAM/fields/Fields/DynamicField/DynamicFieldI.H
+++ b/src/OpenFOAM/fields/Fields/DynamicField/DynamicFieldI.H
@@ -40,7 +40,7 @@ inline void Foam::DynamicField<T, SizeMin>::doAssignDynList
     if (capacity_ < len)
     {
         // Needs more space for the copy operation
-        List<T>::setAddressableSize(capacity_);  // Use entire space
+        List<T>::setAddressableSize(capacity_);
         List<T>::resize_nocopy(len);
         capacity_ = List<T>::size();
     }
@@ -66,19 +66,14 @@ inline void Foam::DynamicField<T, SizeMin>::doCapacity
     // Addressable length, possibly truncated by new capacity
     const label currLen = Foam::min(List<T>::size(), newCapacity);
 
-    // Corner case - see comments in DynamicList doCapacity
-    if (List<T>::size() == newCapacity)
-    {
-        List<T>::setAddressableSize(currLen+1);
-    }
-
+    List<T>::setAddressableSize(capacity_);
     if (nocopy)
     {
         List<T>::resize_nocopy(newCapacity);
     }
     else
     {
-        List<T>::resize(newCapacity);
+        List<T>::resize_copy(currLen, newCapacity);
     }
 
     capacity_ = List<T>::size();
@@ -147,6 +142,19 @@ inline Foam::DynamicField<T, SizeMin>::DynamicField(const label initialCapacity)
 }
 
 
+template<class T, int SizeMin>
+inline Foam::DynamicField<T, SizeMin>::DynamicField
+(
+    const std::pair<label,label>& sizing
+)
+:
+    Field<T>(std::max(sizing.first, sizing.second)),
+    capacity_(Field<T>::size())
+{
+    List<T>::setAddressableSize(sizing.first);
+}
+
+
 template<class T, int SizeMin>
 inline Foam::DynamicField<T, SizeMin>::DynamicField
 (
@@ -163,7 +171,7 @@ template<class T, int SizeMin>
 inline Foam::DynamicField<T, SizeMin>::DynamicField
 (
     const label len,
-    const Foam::zero
+    Foam::zero
 )
 :
     Field<T>(len, Foam::zero{}),
@@ -423,16 +431,6 @@ inline void Foam::DynamicField<T, SizeMin>::setCapacity_nocopy
 }
 
 
-template<class T, int SizeMin>
-inline void Foam::DynamicField<T, SizeMin>::setCapacity_unsafe
-(
-    const label len
-) noexcept
-{
-    capacity_ = len;
-}
-
-
 template<class T, int SizeMin>
 inline void Foam::DynamicField<T, SizeMin>::reserve
 (
@@ -491,6 +489,18 @@ inline void Foam::DynamicField<T, SizeMin>::resize_nocopy
 }
 
 
+template<class T, int SizeMin>
+inline void Foam::DynamicField<T, SizeMin>::resize_fill
+(
+    const label len,
+    const T& val
+)
+{
+    this->doResize(true, len);  // nocopy = true
+    UList<T>::operator=(val);
+}
+
+
 template<class T, int SizeMin>
 inline void Foam::DynamicField<T, SizeMin>::resize
 (
@@ -534,8 +544,7 @@ inline void Foam::DynamicField<T, SizeMin>::shrink_to_fit()
 
     if (currLen < capacity_)
     {
-        // Adjust addressable size to trigger proper resizing
-        List<T>::setAddressableSize(currLen+1);
+        List<T>::setAddressableSize(capacity_);
         List<T>::resize(currLen);
         capacity_ = List<T>::size();
     }
@@ -554,15 +563,6 @@ inline void Foam::DynamicField<T, SizeMin>::shrink_unsafe()
 }
 
 
-template<class T, int SizeMin>
-inline Foam::DynamicField<T, SizeMin>&
-Foam::DynamicField<T, SizeMin>::shrink()
-{
-    this->shrink_to_fit();
-    return *this;
-}
-
-
 template<class T, int SizeMin>
 inline void
 Foam::DynamicField<T, SizeMin>::swap(List<T>& list)
@@ -592,7 +592,7 @@ template<int AnySizeMin>
 inline void Foam::DynamicField<T, SizeMin>::swap
 (
     DynamicField<T, AnySizeMin>& other
-)
+) noexcept
 {
     if
     (
@@ -616,7 +616,7 @@ template<int AnySizeMin>
 inline void Foam::DynamicField<T, SizeMin>::swap
 (
     DynamicList<T, AnySizeMin>& other
-)
+) noexcept
 {
     if
     (
@@ -822,7 +822,7 @@ inline void Foam::DynamicField<T, SizeMin>::operator=
 template<class T, int SizeMin>
 inline void Foam::DynamicField<T, SizeMin>::operator=
 (
-    const Foam::zero
+    Foam::zero
 )
 {
     UList<T>::operator=(Foam::zero{});