diff --git a/Source/cmDocumentVariables.cxx b/Source/cmDocumentVariables.cxx
index 897e516b9..688123606 100644
--- a/Source/cmDocumentVariables.cxx
+++ b/Source/cmDocumentVariables.cxx
@@ -522,6 +522,16 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
      false,
      "Variables That Change Behavior");
 
+    cm->DefineProperty
+    ("CMAKE_INSTALL_DEFAULT_COMPONENT_NAME",  cmProperty::VARIABLE,
+     "Default component used in install() commands.",
+     "If an install() command is used without the COMPONENT argument, "
+     "these files will be grouped into a default component. The name of this "
+     "default install component will be taken from this variable.  "
+     "It defaults to \"Unspecified\". ",
+     false,
+     "Variables That Change Behavior");
+
     cm->DefineProperty
     ("CMAKE_FIND_LIBRARY_PREFIXES",  cmProperty::VARIABLE,
      "Prefixes to prepend when looking for libraries.",