diff --git a/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionConstraint/fixedAxis/fixedAxis.H b/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionConstraint/fixedAxis/fixedAxis.H
index 6a17da99c9..c068bea300 100644
--- a/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionConstraint/fixedAxis/fixedAxis.H
+++ b/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionConstraint/fixedAxis/fixedAxis.H
@@ -25,8 +25,8 @@ Class
     Foam::sixDoFRigidBodyMotionConstraints::fixedAxis
 
 Description
-    sixDoFRigidBodyMotionConstraint.  Axis of body fixed global
-    space.
+    sixDoFRigidBodyMotionConstraint.  Body may only rotate around
+    an axis fixed in global space.
 
 SourceFiles
     fixedAxis.C