diff --git a/src/libcore/fmt/mod.rs b/src/libcore/fmt/mod.rs
index 3d90fe1fa2f21..9c5dbb5e6f356 100644
--- a/src/libcore/fmt/mod.rs
+++ b/src/libcore/fmt/mod.rs
@@ -1618,7 +1618,8 @@ impl<'a> Formatter<'a> {
         self.width
     }
 
-    /// Optionally specified precision for numeric types.
+    /// Optionally specified precision for numeric types. Alternatively, the
+    /// maximum width for string types.
     ///
     /// # Examples
     ///