diff --git a/doc/api/buffer.md b/doc/api/buffer.md
index 69e800ae09e761..1f8e8b5becef62 100644
--- a/doc/api/buffer.md
+++ b/doc/api/buffer.md
@@ -833,7 +833,7 @@ const buf2 = Buffer.from('7468697320697320612074c3a97374', 'hex');
 console.log(buf2.toString());
 ```
 
-A `TypeError` will be thrown if `str` is not a string.
+A `TypeError` will be thrown if `string` is not a string.
 
 ### Class Method: Buffer.isBuffer(obj)
 <!-- YAML