diff --git a/src/corelib/io/qdir.cpp b/src/corelib/io/qdir.cpp
index f7778943c91..5c14d8ffb30 100644
--- a/src/corelib/io/qdir.cpp
+++ b/src/corelib/io/qdir.cpp
@@ -1707,7 +1707,11 @@ bool QDir::isRoot() const
     Returns \c true if \a path is absolute; returns \c false if it is
     relative.
 
-    \sa isAbsolute(), isRelativePath(), makeAbsolute(), cleanPath()
+    \note If \a path starts with ':', this function will return \c true
+    because paths starting with ':' are treated specially as they denote
+    a QResource.
+
+    \sa isAbsolute(), isRelativePath(), makeAbsolute(), cleanPath(), QResource
 */
 
 /*!