diff --git a/documentation/style-guide.rst b/documentation/style-guide.rst
index 0078d670e..8e043895b 100644
--- a/documentation/style-guide.rst
+++ b/documentation/style-guide.rst
@@ -87,6 +87,9 @@ Unix
    The name of the operating system developed at AT&T Bell Labs in the early
    1970s.
 
+
+.. index:: diataxis
+
 Diátaxis
 ========