diff --git a/doc/design.rst b/doc/design.rst
index a58f803ea..1e00a3358 100644
--- a/doc/design.rst
+++ b/doc/design.rst
@@ -48,7 +48,7 @@ be used instead of the complete filename.
 Apart from the files stored within the ``keys`` and ``data`` directories,
 all files are encrypted with AES-256 in counter mode (CTR). The integrity
 of the encrypted data is secured by a Poly1305-AES message authentication
-code (sometimes also referred to as a "signature").
+code (MAC).
 Files in the ``data`` directory ("pack files") consist of multiple parts
 which are all independently encrypted and authenticated, see below.