builtin -> built-in.
diff --git a/Doc/library/heapq.rst b/Doc/library/heapq.rst
index bf7e3c4..9a44047 100644
--- a/Doc/library/heapq.rst
+++ b/Doc/library/heapq.rst
@@ -147,7 +147,7 @@
 
 The latter two functions perform best for smaller values of *n*.  For larger
 values, it is more efficient to use the :func:`sorted` function.  Also, when
-``n==1``, it is more efficient to use the builtin :func:`min` and :func:`max`
+``n==1``, it is more efficient to use the built-in :func:`min` and :func:`max`
 functions.