diff --git a/src/librustc/hir/mod.rs b/src/librustc/hir/mod.rs
index 8941158e561d1..24c145b3811e3 100644
--- a/src/librustc/hir/mod.rs
+++ b/src/librustc/hir/mod.rs
@@ -1233,7 +1233,7 @@ pub struct Arm {
     pub pats: HirVec<P<Pat>>,
     /// Optional guard clause.
     pub guard: Option<Guard>,
-    /// The action to take if this arm matches.
+    /// The expression the arm evaluates to if this arm matches.
     pub body: P<Expr>,
 }