diff --git a/stdlib/public/core/StringProtocol.swift b/stdlib/public/core/StringProtocol.swift
index 9523b3db7f360..eac94b5a6ecb7 100644
--- a/stdlib/public/core/StringProtocol.swift
+++ b/stdlib/public/core/StringProtocol.swift
@@ -43,7 +43,7 @@ public protocol StringProtocol
   var unicodeScalars: UnicodeScalarView { get }
 
   func hasPrefix(_ prefix: String) -> Bool
-  func hasSuffix(_ prefix: String) -> Bool
+  func hasSuffix(_ suffix: String) -> Bool
 
   func lowercased() -> String
   func uppercased() -> String