diff --git a/library/core/src/task/poll.rs b/library/core/src/task/poll.rs
index ca668361ef63b..59ffe7ad49c05 100644
--- a/library/core/src/task/poll.rs
+++ b/library/core/src/task/poll.rs
@@ -125,7 +125,7 @@ impl<T, E> Poll<Result<T, E>> {
         }
     }
 
-    /// Maps a `Poll::Ready<Result<T, E>>` to `Poll::Ready<Result<T, F>>` by
+    /// Maps a `Poll::Ready<Result<T, E>>` to `Poll::Ready<Result<T, U>>` by
     /// applying a function to a contained `Poll::Ready(Err)` value, leaving all other
     /// variants untouched.
     ///