diff --git a/pep-0307.txt b/pep-0307.txt
index 3d8859fcf..3b4659e8c 100644
--- a/pep-0307.txt
+++ b/pep-0307.txt
@@ -80,7 +80,8 @@ Protocol versions
     Several functions, methods and constructors used for pickling used
     to take a positional argument named 'bin' which was a flag,
     defaulting to 0, indicating binary mode.  This argument is renamed
-    to 'proto' and now gives the protocol number, still defaulting to 0.
+    to 'protocol' and now gives the protocol number, still defaulting
+    to 0.
 
     It so happens that passing 2 for the 'bin' argument in previous
     Python versions had the same effect as passing 1.  Nevertheless, a