diff --git a/src/sampling/sampledSurface/writers/dx/dxSurfaceWriter.C b/src/sampling/sampledSurface/writers/dx/dxSurfaceWriter.C
index a5c613b15d..49e088bb83 100644
--- a/src/sampling/sampledSurface/writers/dx/dxSurfaceWriter.C
+++ b/src/sampling/sampledSurface/writers/dx/dxSurfaceWriter.C
@@ -249,7 +249,7 @@ void Foam::dxSurfaceWriter<Type>::write
     const fileName& surfaceName,
     const pointField& points,
     const faceList& faces,
-    const fileName& fieldName,
+    const word& fieldName,
     const Field<Type>& values,
     const bool verbose
 ) const
diff --git a/src/sampling/sampledSurface/writers/dx/dxSurfaceWriter.H b/src/sampling/sampledSurface/writers/dx/dxSurfaceWriter.H
index fcce2e6af2..8dc9164ec2 100644
--- a/src/sampling/sampledSurface/writers/dx/dxSurfaceWriter.H
+++ b/src/sampling/sampledSurface/writers/dx/dxSurfaceWriter.H
@@ -88,7 +88,7 @@ public:
             const fileName& surfaceName,
             const pointField& points,
             const faceList& faces,
-            const fileName& fieldName,
+            const word& fieldName,
             const Field<Type>& values,
             const bool verbose = false
         ) const;
diff --git a/src/sampling/sampledSurface/writers/foamFile/foamFileSurfaceWriter.C b/src/sampling/sampledSurface/writers/foamFile/foamFileSurfaceWriter.C
index 0d68df2044..7f617911c6 100644
--- a/src/sampling/sampledSurface/writers/foamFile/foamFileSurfaceWriter.C
+++ b/src/sampling/sampledSurface/writers/foamFile/foamFileSurfaceWriter.C
@@ -84,7 +84,7 @@ void Foam::foamFileSurfaceWriter<Type>::write
     const fileName& surfaceName,
     const pointField& points,
     const faceList& faces,
-    const fileName& fieldName,
+    const word& fieldName,
     const Field<Type>& values,
     const bool verbose
 ) const
diff --git a/src/sampling/sampledSurface/writers/foamFile/foamFileSurfaceWriter.H b/src/sampling/sampledSurface/writers/foamFile/foamFileSurfaceWriter.H
index 207f36c962..8ef12cda31 100644
--- a/src/sampling/sampledSurface/writers/foamFile/foamFileSurfaceWriter.H
+++ b/src/sampling/sampledSurface/writers/foamFile/foamFileSurfaceWriter.H
@@ -95,7 +95,7 @@ public:
             const fileName& surfaceName,
             const pointField& points,
             const faceList& faces,
-            const fileName& fieldName,
+            const word& fieldName,
             const Field<Type>& values,
             const bool verbose = false
         ) const;
diff --git a/src/sampling/sampledSurface/writers/null/nullSurfaceWriter.C b/src/sampling/sampledSurface/writers/null/nullSurfaceWriter.C
index 1409750c05..56fcaad321 100644
--- a/src/sampling/sampledSurface/writers/null/nullSurfaceWriter.C
+++ b/src/sampling/sampledSurface/writers/null/nullSurfaceWriter.C
@@ -53,7 +53,7 @@ void Foam::nullSurfaceWriter<Type>::write
     const fileName& surfaceName,
     const pointField& points,
     const faceList& faces,
-    const fileName& fieldName,
+    const word& fieldName,
     const Field<Type>& values,
     const bool verbose
 ) const
diff --git a/src/sampling/sampledSurface/writers/null/nullSurfaceWriter.H b/src/sampling/sampledSurface/writers/null/nullSurfaceWriter.H
index 24a3f70d4c..475617d48b 100644
--- a/src/sampling/sampledSurface/writers/null/nullSurfaceWriter.H
+++ b/src/sampling/sampledSurface/writers/null/nullSurfaceWriter.H
@@ -80,7 +80,7 @@ public:
             const fileName& surfaceName,
             const pointField& points,
             const faceList& faces,
-            const fileName& fieldName,
+            const word& fieldName,
             const Field<Type>& values,
             const bool verbose = false
         ) const;
diff --git a/src/sampling/sampledSurface/writers/proxy/proxySurfaceWriter.H b/src/sampling/sampledSurface/writers/proxy/proxySurfaceWriter.H
index ceeec731a7..e0dd1dc596 100644
--- a/src/sampling/sampledSurface/writers/proxy/proxySurfaceWriter.H
+++ b/src/sampling/sampledSurface/writers/proxy/proxySurfaceWriter.H
@@ -102,7 +102,7 @@ public:
             const fileName& surfaceName,
             const pointField& points,
             const faceList& faces,
-            const fileName& fieldName,
+            const word& fieldName,
             const Field<Type>& values,
             const bool verbose = false
         ) const
diff --git a/src/sampling/sampledSurface/writers/raw/rawSurfaceWriter.C b/src/sampling/sampledSurface/writers/raw/rawSurfaceWriter.C
index bab2ad38f3..c916fe16c3 100644
--- a/src/sampling/sampledSurface/writers/raw/rawSurfaceWriter.C
+++ b/src/sampling/sampledSurface/writers/raw/rawSurfaceWriter.C
@@ -65,7 +65,7 @@ void Foam::rawSurfaceWriter<Type>::writeGeometry
 template<class Type>
 void Foam::rawSurfaceWriter<Type>::writeData
 (
-    const fileName& fieldName,
+    const word& fieldName,
     const pointField& points,
     const faceList& faces,
     const scalarField& values,
@@ -101,7 +101,7 @@ void Foam::rawSurfaceWriter<Type>::writeData
 template<class Type>
 void Foam::rawSurfaceWriter<Type>::writeData
 (
-    const fileName& fieldName,
+    const word& fieldName,
     const pointField& points,
     const faceList& faces,
     const vectorField& values,
@@ -144,7 +144,7 @@ void Foam::rawSurfaceWriter<Type>::writeData
 template<class Type>
 void Foam::rawSurfaceWriter<Type>::writeData
 (
-    const fileName& fieldName,
+    const word& fieldName,
     const pointField& points,
     const faceList& faces,
     const sphericalTensorField& values,
@@ -183,7 +183,7 @@ void Foam::rawSurfaceWriter<Type>::writeData
 template<class Type>
 void Foam::rawSurfaceWriter<Type>::writeData
 (
-    const fileName& fieldName,
+    const word& fieldName,
     const pointField& points,
     const faceList& faces,
     const symmTensorField& values,
@@ -232,7 +232,7 @@ void Foam::rawSurfaceWriter<Type>::writeData
 template<class Type>
 void Foam::rawSurfaceWriter<Type>::writeData
 (
-    const fileName& fieldName,
+    const word& fieldName,
     const pointField& points,
     const faceList& faces,
     const tensorField& values,
@@ -344,7 +344,7 @@ namespace Foam
         const fileName& surfaceName,
         const pointField& points,
         const faceList& faces,
-        const fileName& fieldName,
+        const word& fieldName,
         const Field<bool>& values,
         const bool verbose
     ) const
@@ -359,7 +359,7 @@ void Foam::rawSurfaceWriter<Type>::write
     const fileName& surfaceName,
     const pointField& points,
     const faceList& faces,
-    const fileName& fieldName,
+    const word& fieldName,
     const Field<Type>& values,
     const bool verbose
 ) const
diff --git a/src/sampling/sampledSurface/writers/raw/rawSurfaceWriter.H b/src/sampling/sampledSurface/writers/raw/rawSurfaceWriter.H
index fc9fc0804a..353399c893 100644
--- a/src/sampling/sampledSurface/writers/raw/rawSurfaceWriter.H
+++ b/src/sampling/sampledSurface/writers/raw/rawSurfaceWriter.H
@@ -70,7 +70,7 @@ class rawSurfaceWriter
 
         static void writeData
         (
-            const fileName& fieldName,
+            const word& fieldName,
             const pointField& points,
             const faceList& faces,
             const scalarField& values,
@@ -79,7 +79,7 @@ class rawSurfaceWriter
 
         static void writeData
         (
-            const fileName& fieldName,
+            const word& fieldName,
             const pointField& points,
             const faceList& faces,
             const vectorField& values,
@@ -88,7 +88,7 @@ class rawSurfaceWriter
 
         static void writeData
         (
-            const fileName& fieldName,
+            const word& fieldName,
             const pointField& points,
             const faceList& faces,
             const sphericalTensorField& values,
@@ -97,7 +97,7 @@ class rawSurfaceWriter
 
         static void writeData
         (
-            const fileName& fieldName,
+            const word& fieldName,
             const pointField& points,
             const faceList& faces,
             const symmTensorField& values,
@@ -106,7 +106,7 @@ class rawSurfaceWriter
 
         static void writeData
         (
-            const fileName& fieldName,
+            const word& fieldName,
             const pointField& points,
             const faceList& faces,
             const tensorField& values,
@@ -152,7 +152,7 @@ public:
             const fileName& surfaceName,
             const pointField& points,
             const faceList& faces,
-            const fileName& fieldName,
+            const word& fieldName,
             const Field<Type>& values,
             const bool verbose = false
         ) const;
diff --git a/src/sampling/sampledSurface/writers/surfaceWriter.H b/src/sampling/sampledSurface/writers/surfaceWriter.H
index b645c522ef..0bee6afe8a 100644
--- a/src/sampling/sampledSurface/writers/surfaceWriter.H
+++ b/src/sampling/sampledSurface/writers/surfaceWriter.H
@@ -128,7 +128,7 @@ public:
             const fileName& surfaceName,    // name of surface
             const pointField& points,
             const faceList& faces,
-            const fileName& fieldName,      // name of field
+            const word& fieldName,          // name of field
             const Field<Type>& values,
             const bool verbose = false
         ) const = 0;
diff --git a/src/sampling/sampledSurface/writers/vtk/vtkSurfaceWriter.C b/src/sampling/sampledSurface/writers/vtk/vtkSurfaceWriter.C
index 7ecfd6949d..5967a54211 100644
--- a/src/sampling/sampledSurface/writers/vtk/vtkSurfaceWriter.C
+++ b/src/sampling/sampledSurface/writers/vtk/vtkSurfaceWriter.C
@@ -266,7 +266,7 @@ void Foam::vtkSurfaceWriter<Type>::write
     const fileName& surfaceName,
     const pointField& points,
     const faceList& faces,
-    const fileName& fieldName,
+    const word& fieldName,
     const Field<Type>& values,
     const bool verbose
 ) const
diff --git a/src/sampling/sampledSurface/writers/vtk/vtkSurfaceWriter.H b/src/sampling/sampledSurface/writers/vtk/vtkSurfaceWriter.H
index 1b8736f103..da0c3ef589 100644
--- a/src/sampling/sampledSurface/writers/vtk/vtkSurfaceWriter.H
+++ b/src/sampling/sampledSurface/writers/vtk/vtkSurfaceWriter.H
@@ -97,7 +97,7 @@ public:
             const fileName& surfaceName,
             const pointField& points,
             const faceList& faces,
-            const fileName& fieldName,
+            const word& fieldName,
             const Field<Type>& values,
             const bool verbose = false
         ) const;