diff --git a/Include/abstract.h b/Include/abstract.h
index fcb5fe6..53b4193 100644
--- a/Include/abstract.h
+++ b/Include/abstract.h
@@ -621,7 +621,7 @@
 
        */
 
-     int PySequence_Lenth Py_PROTO((PyObject *o));
+     int PySequence_Length Py_PROTO((PyObject *o));
 
        /*
          Return the length of sequence object o, or -1 on failure.