diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs
index 3da992dca30ee..e2cc99813aca5 100644
--- a/src/libcore/str/mod.rs
+++ b/src/libcore/str/mod.rs
@@ -2325,7 +2325,7 @@ impl str {
         i.get_mut(self)
     }
 
-    /// Returns a unchecked subslice of `str`.
+    /// Returns an unchecked subslice of `str`.
     ///
     /// This is the unchecked alternative to indexing the `str`.
     ///