diff --git a/src/conversion/ccm/reader/ccmReader.H b/src/conversion/ccm/reader/ccmReader.H
index 283005fd6d..c1e66415ed 100644
--- a/src/conversion/ccm/reader/ccmReader.H
+++ b/src/conversion/ccm/reader/ccmReader.H
@@ -206,7 +206,7 @@ private:
     // Private Data
 
         //- Reader options
-        const unique_ptr<options> options_;
+        const std::unique_ptr<options> options_;
 
 
         //- Enumeration defining the status of a ccmio node
diff --git a/src/conversion/ccm/writer/ccmWriter.H b/src/conversion/ccm/writer/ccmWriter.H
index 2a2127da4f..b62eadf910 100644
--- a/src/conversion/ccm/writer/ccmWriter.H
+++ b/src/conversion/ccm/writer/ccmWriter.H
@@ -133,7 +133,7 @@ class writer
     // Member Data
 
         //- MapIds for various components (cell, internalFaces, boundaries)
-        unique_ptr<ccmMaps> maps_;
+        std::unique_ptr<ccmMaps> maps_;
 
         //- mesh reference
         const polyMesh& mesh_;
diff --git a/src/conversion/common/reader/meshReader.H b/src/conversion/common/reader/meshReader.H
index 839f174755..68baf6a775 100644
--- a/src/conversion/common/reader/meshReader.H
+++ b/src/conversion/common/reader/meshReader.H
@@ -122,7 +122,7 @@ private:
         //- Point-cell addressing. Used for topological analysis
         // Warning. This point cell addressing list potentially contains
         // duplicate cell entries. Use additional checking
-        mutable unique_ptr<labelListList> pointCellsPtr_;
+        mutable std::unique_ptr<labelListList> pointCellsPtr_;
 
         //- Association between two faces
         List<labelPair> interfaces_;
diff --git a/src/dynamicMesh/attachDetach/attachDetach.H b/src/dynamicMesh/attachDetach/attachDetach.H
index 1056a4acac..eecc3f1ba0 100644
--- a/src/dynamicMesh/attachDetach/attachDetach.H
+++ b/src/dynamicMesh/attachDetach/attachDetach.H
@@ -105,7 +105,7 @@ class attachDetach
         // Private addressing data.  Created on topology change
 
         //- Map of matching points
-        mutable unique_ptr<Map<label>> pointMatchMapPtr_;
+        mutable std::unique_ptr<Map<label>> pointMatchMapPtr_;
 
 
     // Private Member Functions
diff --git a/src/dynamicMesh/boundaryMesh/boundaryMesh.C b/src/dynamicMesh/boundaryMesh/boundaryMesh.C
index cfae3a345c..c98d1c6dbe 100644
--- a/src/dynamicMesh/boundaryMesh/boundaryMesh.C
+++ b/src/dynamicMesh/boundaryMesh/boundaryMesh.C
@@ -1806,7 +1806,7 @@ void Foam::boundaryMesh::changeFaces
 
     // Reconstruct 'mesh' from new faces and (copy of) existing points.
 
-    unique_ptr<bMesh> newMeshPtr(new bMesh(newFaces, mesh().points()));
+    std::unique_ptr<bMesh> newMeshPtr(new bMesh(newFaces, mesh().points()));
 
     // Reset meshFace_ to new ordering.
     meshFace_.transfer(newMeshFace);
diff --git a/src/dynamicMesh/boundaryMesh/boundaryMesh.H b/src/dynamicMesh/boundaryMesh/boundaryMesh.H
index 9540d59af6..0b20ef4100 100644
--- a/src/dynamicMesh/boundaryMesh/boundaryMesh.H
+++ b/src/dynamicMesh/boundaryMesh/boundaryMesh.H
@@ -77,7 +77,7 @@ class boundaryMesh
     // Private Data
 
         //- All boundary mesh data. Reconstructed every time faces are repatched
-        unique_ptr<bMesh> meshPtr_;
+        std::unique_ptr<bMesh> meshPtr_;
 
         //- Patches. Reconstructed every time faces are repatched.
         PtrList<boundaryPatch> patches_;
diff --git a/src/dynamicMesh/layerAdditionRemoval/layerAdditionRemoval.H b/src/dynamicMesh/layerAdditionRemoval/layerAdditionRemoval.H
index 2cb206a7a4..25e5e68327 100644
--- a/src/dynamicMesh/layerAdditionRemoval/layerAdditionRemoval.H
+++ b/src/dynamicMesh/layerAdditionRemoval/layerAdditionRemoval.H
@@ -77,10 +77,10 @@ class layerAdditionRemoval
         mutable scalar oldLayerThickness_;
 
         //- Point pairing
-        mutable unique_ptr<labelList> pointsPairingPtr_;
+        mutable std::unique_ptr<labelList> pointsPairingPtr_;
 
         //- Face pairing
-        mutable unique_ptr<labelList> facesPairingPtr_;
+        mutable std::unique_ptr<labelList> facesPairingPtr_;
 
         //- Layer removal trigger time index
         mutable label triggerRemoval_;
diff --git a/src/dynamicMesh/meshCut/cellCuts/cellCuts.H b/src/dynamicMesh/meshCut/cellCuts/cellCuts.H
index 6b020fe730..e3fc64798b 100644
--- a/src/dynamicMesh/meshCut/cellCuts/cellCuts.H
+++ b/src/dynamicMesh/meshCut/cellCuts/cellCuts.H
@@ -134,7 +134,7 @@ class cellCuts
 
             //- Cuts per existing face (includes those along edge of face)
             //  Cuts in no particular order.
-            mutable unique_ptr<labelListList> faceCutsPtr_;
+            mutable std::unique_ptr<labelListList> faceCutsPtr_;
 
             //- Per face : cut across edge (so not along existing edge)
             //  (can only be one per face)
diff --git a/src/dynamicMesh/polyMeshAdder/faceCoupleInfo.H b/src/dynamicMesh/polyMeshAdder/faceCoupleInfo.H
index e21c5323f4..721dd6b453 100644
--- a/src/dynamicMesh/polyMeshAdder/faceCoupleInfo.H
+++ b/src/dynamicMesh/polyMeshAdder/faceCoupleInfo.H
@@ -165,10 +165,10 @@ class faceCoupleInfo
         static const scalar angleTol_;
 
         //- Master patch
-        unique_ptr<indirectPrimitivePatch> masterPatchPtr_;
+        std::unique_ptr<indirectPrimitivePatch> masterPatchPtr_;
 
         //- Slave patch
-        unique_ptr<indirectPrimitivePatch> slavePatchPtr_;
+        std::unique_ptr<indirectPrimitivePatch> slavePatchPtr_;
 
 
         //- Description of cut.
@@ -186,7 +186,7 @@ class faceCoupleInfo
         //  Orientation of cutFaces should be same as masterFaces!
         pointField cutPoints_;
 
-        unique_ptr<primitiveFacePatch> cutFacesPtr_;
+        std::unique_ptr<primitiveFacePatch> cutFacesPtr_;
 
         //- Additional point coupling information. Is between points on
         //  boundary of both meshes.
diff --git a/src/dynamicMesh/slidingInterface/enrichedPatch/enrichedPatch.H b/src/dynamicMesh/slidingInterface/enrichedPatch/enrichedPatch.H
index a67de9d114..bec45a2d29 100644
--- a/src/dynamicMesh/slidingInterface/enrichedPatch/enrichedPatch.H
+++ b/src/dynamicMesh/slidingInterface/enrichedPatch/enrichedPatch.H
@@ -99,38 +99,38 @@ class enrichedPatch
     // Demand-driven private data
 
         //- Enriched patch
-        mutable unique_ptr<faceList> enrichedFacesPtr_;
+        mutable std::unique_ptr<faceList> enrichedFacesPtr_;
 
         //- Mesh points
-        mutable unique_ptr<labelList> meshPointsPtr_;
+        mutable std::unique_ptr<labelList> meshPointsPtr_;
 
         //- Local faces
-        mutable unique_ptr<faceList> localFacesPtr_;
+        mutable std::unique_ptr<faceList> localFacesPtr_;
 
         //- Local points
-        mutable unique_ptr<pointField> localPointsPtr_;
+        mutable std::unique_ptr<pointField> localPointsPtr_;
 
         //- Point-point addressing
-        mutable unique_ptr<labelListList> pointPointsPtr_;
+        mutable std::unique_ptr<labelListList> pointPointsPtr_;
 
         // Master point addressing
-        mutable unique_ptr<Map<labelList>> masterPointFacesPtr_;
+        mutable std::unique_ptr<Map<labelList>> masterPointFacesPtr_;
 
 
         // Cut faces and addressing
 
             //- Cut faces
-            mutable unique_ptr<faceList> cutFacesPtr_;
+            mutable std::unique_ptr<faceList> cutFacesPtr_;
 
             //- Cut face master
             //  - the face on the master patch for internal faces
             //  - the creator face for boundary face
-            mutable unique_ptr<labelList> cutFaceMasterPtr_;
+            mutable std::unique_ptr<labelList> cutFaceMasterPtr_;
 
             //- Cut face slave
             //  - the face on the slave patch for internal faces
             //  - -1 for boundary face
-            mutable unique_ptr<labelList> cutFaceSlavePtr_;
+            mutable std::unique_ptr<labelList> cutFaceSlavePtr_;
 
 
     // Private Member Functions
diff --git a/src/dynamicMesh/slidingInterface/slidingInterface.H b/src/dynamicMesh/slidingInterface/slidingInterface.H
index 064a5e49f7..f3ac02bf52 100644
--- a/src/dynamicMesh/slidingInterface/slidingInterface.H
+++ b/src/dynamicMesh/slidingInterface/slidingInterface.H
@@ -161,53 +161,53 @@ private:
             //- Cut face master face.  Gives the index of face in master patch
             //  the cut face has been created from.  For a slave-only face
             //  this will be -1
-            mutable unique_ptr<labelList> cutFaceMasterPtr_;
+            mutable std::unique_ptr<labelList> cutFaceMasterPtr_;
 
             //- Cut face slave face.  Gives the index of face in slave patch
             //  the cut face has been created from.  For a master-only face
             //  this will be -1
-            mutable unique_ptr<labelList> cutFaceSlavePtr_;
+            mutable std::unique_ptr<labelList> cutFaceSlavePtr_;
 
             //- Master zone faceCells
-            mutable unique_ptr<labelList> masterFaceCellsPtr_;
+            mutable std::unique_ptr<labelList> masterFaceCellsPtr_;
 
             //- Slave zone faceCells
-            mutable unique_ptr<labelList> slaveFaceCellsPtr_;
+            mutable std::unique_ptr<labelList> slaveFaceCellsPtr_;
 
             //- Master stick-out faces
-            mutable unique_ptr<labelList> masterStickOutFacesPtr_;
+            mutable std::unique_ptr<labelList> masterStickOutFacesPtr_;
 
             //- Slave stick-out faces
-            mutable unique_ptr<labelList> slaveStickOutFacesPtr_;
+            mutable std::unique_ptr<labelList> slaveStickOutFacesPtr_;
 
             //- Retired point mapping.
             //  For every retired slave side point, gives the label of the
             //  master point that replaces it
-            mutable unique_ptr<Map<label>> retiredPointMapPtr_;
+            mutable std::unique_ptr<Map<label>> retiredPointMapPtr_;
 
             //- Cut edge pairs
             //  For cut points created by intersection two edges,
             //  store the master-slave edge pair used in creation
-            mutable unique_ptr<Map<Pair<edge>>> cutPointEdgePairMapPtr_;
+            mutable std::unique_ptr<Map<Pair<edge>>> cutPointEdgePairMapPtr_;
 
             //- Slave point hit.  The index of master point hit by the
             //  slave point in projection.  For no point hit, set to -1
-            mutable unique_ptr<labelList> slavePointPointHitsPtr_;
+            mutable std::unique_ptr<labelList> slavePointPointHitsPtr_;
 
             //- Slave edge hit.  The index of master edge hit by the
             //  slave point in projection.  For point or no edge  hit, set to -1
-            mutable unique_ptr<labelList> slavePointEdgeHitsPtr_;
+            mutable std::unique_ptr<labelList> slavePointEdgeHitsPtr_;
 
             //- Slave face hit.  The index of master face hit by the
             //  slave point in projection.
-            mutable unique_ptr<List<objectHit>> slavePointFaceHitsPtr_;
+            mutable std::unique_ptr<List<objectHit>> slavePointFaceHitsPtr_;
 
             //- Master point edge hit.  The index of slave edge hit by
             //  a master point.  For no hit set to -1
-            mutable unique_ptr<labelList> masterPointEdgeHitsPtr_;
+            mutable std::unique_ptr<labelList> masterPointEdgeHitsPtr_;
 
             //- Projected slave points
-            mutable unique_ptr<pointField> projectedSlavePointsPtr_;
+            mutable std::unique_ptr<pointField> projectedSlavePointsPtr_;
 
 
     // Private Member Functions
diff --git a/src/dynamicMesh/slidingInterface/slidingInterfaceAttachedAddressing.C b/src/dynamicMesh/slidingInterface/slidingInterfaceAttachedAddressing.C
index f7e43abc34..38e8647b6b 100644
--- a/src/dynamicMesh/slidingInterface/slidingInterfaceAttachedAddressing.C
+++ b/src/dynamicMesh/slidingInterface/slidingInterfaceAttachedAddressing.C
@@ -278,7 +278,7 @@ void Foam::slidingInterface::renumberAttachedAddressing
     const labelList& sfc = slaveFaceCells();
 
     // Master side
-    unique_ptr<labelList> newMfcPtr(new labelList(mfc.size(), -1));
+    std::unique_ptr<labelList> newMfcPtr(new labelList(mfc.size(), -1));
     auto& newMfc = *newMfcPtr;
 
     const labelList& mfzRenumber =
@@ -295,7 +295,7 @@ void Foam::slidingInterface::renumberAttachedAddressing
     }
 
     // Slave side
-    unique_ptr<labelList> newSfcPtr(new labelList(sfc.size(), -1));
+    std::unique_ptr<labelList> newSfcPtr(new labelList(sfc.size(), -1));
     auto& newSfc = *newSfcPtr;
 
     const labelList& sfzRenumber =
@@ -331,7 +331,7 @@ void Foam::slidingInterface::renumberAttachedAddressing
     // Master side
     const labelList& msof = masterStickOutFaces();
 
-    unique_ptr<labelList> newMsofPtr(new labelList(msof.size(), -1));
+    std::unique_ptr<labelList> newMsofPtr(new labelList(msof.size(), -1));
     auto& newMsof = *newMsofPtr;
 
     forAll(msof, facei)
@@ -347,7 +347,7 @@ void Foam::slidingInterface::renumberAttachedAddressing
     // Slave side
     const labelList& ssof = slaveStickOutFaces();
 
-    unique_ptr<labelList> newSsofPtr(new labelList(ssof.size(), -1));
+    std::unique_ptr<labelList> newSsofPtr(new labelList(ssof.size(), -1));
     auto& newSsof = *newSsofPtr;
 
     forAll(ssof, facei)
@@ -376,7 +376,7 @@ void Foam::slidingInterface::renumberAttachedAddressing
     // Renumber the retired point map. Need to take a copy!
     const Map<label> rpm = retiredPointMap();
 
-    unique_ptr<Map<label>> newRpmPtr(new Map<label>(rpm.size()));
+    std::unique_ptr<Map<label>> newRpmPtr(new Map<label>(rpm.size()));
     auto& newRpm = *newRpmPtr;
 
     // Get reference to point renumbering
@@ -406,7 +406,10 @@ void Foam::slidingInterface::renumberAttachedAddressing
     // Renumber the cut point edge pair map. Need to take a copy!
     const Map<Pair<edge>> cpepm = cutPointEdgePairMap();
 
-    unique_ptr<Map<Pair<edge>>> newCpepmPtr(new Map<Pair<edge>>(cpepm.size()));
+    std::unique_ptr<Map<Pair<edge>>> newCpepmPtr
+    (
+        new Map<Pair<edge>>(cpepm.size())
+    );
     auto& newCpepm = *newCpepmPtr;
 
     forAllConstIters(cpepm, iter)
@@ -447,7 +450,7 @@ void Foam::slidingInterface::renumberAttachedAddressing
     // Renumber the projected slave zone points
     const pointField& projectedSlavePoints = *projectedSlavePointsPtr_;
 
-    unique_ptr<pointField> newProjectedSlavePointsPtr
+    std::unique_ptr<pointField> newProjectedSlavePointsPtr
     (
         new pointField(projectedSlavePoints.size())
     );
diff --git a/src/lumpedPointMotion/state/lumpedPointState.H b/src/lumpedPointMotion/state/lumpedPointState.H
index 2871bf240a..68dbe37782 100644
--- a/src/lumpedPointMotion/state/lumpedPointState.H
+++ b/src/lumpedPointMotion/state/lumpedPointState.H
@@ -122,7 +122,7 @@ private:
         bool degrees_;
 
         //- Tensor rotation of lumped points
-        mutable unique_ptr<tensorField> rotationPtr_;
+        mutable std::unique_ptr<tensorField> rotationPtr_;
 
 
     // Private Member Functions
diff --git a/src/meshTools/edgeMesh/edgeMesh.H b/src/meshTools/edgeMesh/edgeMesh.H
index dca67bfb6a..57f066ea35 100644
--- a/src/meshTools/edgeMesh/edgeMesh.H
+++ b/src/meshTools/edgeMesh/edgeMesh.H
@@ -80,7 +80,7 @@ class edgeMesh
         edgeList edges_;
 
         //- From point to edges
-        mutable unique_ptr<labelListList> pointEdgesPtr_;
+        mutable std::unique_ptr<labelListList> pointEdgesPtr_;
 
 
     // Private Member Functions
diff --git a/src/meshTools/edgeMesh/extendedEdgeMesh/extendedEdgeMesh.H b/src/meshTools/edgeMesh/extendedEdgeMesh/extendedEdgeMesh.H
index 3eb6d3395f..f495b8e8f6 100644
--- a/src/meshTools/edgeMesh/extendedEdgeMesh/extendedEdgeMesh.H
+++ b/src/meshTools/edgeMesh/extendedEdgeMesh/extendedEdgeMesh.H
@@ -193,10 +193,10 @@ protected:
         labelList regionEdges_;
 
         //- Search tree for all feature points
-        mutable unique_ptr<indexedOctree<treeDataPoint>> pointTree_;
+        mutable std::unique_ptr<indexedOctree<treeDataPoint>> pointTree_;
 
         //- Search tree for all edges
-        mutable unique_ptr<indexedOctree<treeDataEdge>> edgeTree_;
+        mutable std::unique_ptr<indexedOctree<treeDataEdge>> edgeTree_;
 
         //- Individual search trees for each type of edge
         mutable PtrList<indexedOctree<treeDataEdge>> edgeTreesByType_;
diff --git a/src/sampling/meshToMesh0/meshToMesh0.H b/src/sampling/meshToMesh0/meshToMesh0.H
index 6f54e45eb1..85a3c3b895 100644
--- a/src/sampling/meshToMesh0/meshToMesh0.H
+++ b/src/sampling/meshToMesh0/meshToMesh0.H
@@ -91,13 +91,13 @@ class meshToMesh0
         labelListList boundaryAddressing_;
 
         //- Inverse-distance interpolation weights
-        mutable unique_ptr<scalarListList> inverseDistanceWeightsPtr_;
+        mutable std::unique_ptr<scalarListList> inverseDistanceWeightsPtr_;
 
         //- Inverse-volume interpolation weights
-        mutable unique_ptr<scalarListList> inverseVolumeWeightsPtr_;
+        mutable std::unique_ptr<scalarListList> inverseVolumeWeightsPtr_;
 
         //- Cell to cell overlap addressing
-        mutable unique_ptr<labelListList> cellToCellAddressingPtr_;
+        mutable std::unique_ptr<labelListList> cellToCellAddressingPtr_;
 
         //- Overlap volume
         mutable scalar V_;
diff --git a/src/surfMesh/triSurface/triSurface.H b/src/surfMesh/triSurface/triSurface.H
index 770c08f8c4..899d76ecd9 100644
--- a/src/surfMesh/triSurface/triSurface.H
+++ b/src/surfMesh/triSurface/triSurface.H
@@ -95,11 +95,11 @@ class triSurface
     // Demand Driven
 
         //- Edge-face addressing (sorted)
-        mutable unique_ptr<labelListList> sortedEdgeFacesPtr_;
+        mutable std::unique_ptr<labelListList> sortedEdgeFacesPtr_;
 
         //- Label of face that 'owns' edge
         //- i.e. e.vec() is righthanded walk along face
-        mutable unique_ptr<labelList> edgeOwnerPtr_;
+        mutable std::unique_ptr<labelList> edgeOwnerPtr_;
 
 
     // Private Member Functions