diff --git a/Doc/library/math.rst b/Doc/library/math.rst
index d297c78..93f24e3 100644
--- a/Doc/library/math.rst
+++ b/Doc/library/math.rst
@@ -318,6 +318,14 @@
    .. versionadded:: 2.7
 
 
+.. function:: lgamma(x)
+
+   Return the natural logarithm of the absolute value of the Gamma
+   function at *x*.
+
+   .. versionadded:: 2.7
+
+
 Constants
 ---------