diff --git a/doc/overlays.xml b/doc/overlays.xml
index abaa264addb7..4ad2764f33f9 100644
--- a/doc/overlays.xml
+++ b/doc/overlays.xml
@@ -5,7 +5,7 @@
 <title>Overlays</title>
 
 <para>This chapter describes how to extend and change Nixpkgs content using
-overlays.  Overlays are used to add phases in the fix-point used by Nixpkgs
+overlays.  Overlays are used to add layers in the fix-point used by Nixpkgs
 to bind the dependencies of all packages.</para>
 
 <!--============================================================-->