diff --git a/glossary.tex b/glossary.tex
index 449cb3529dc57ef359c481ec85d53a39b07d6fd1..6646601c751c43b0187b7a3d34ef9e7f40cf0865 100644
--- a/glossary.tex
+++ b/glossary.tex
@@ -287,7 +287,8 @@
   description={work as the ``battery power'' of a magic user, which allows them to power spells},
   shortplural={MP},
   name={Mana Points (MP)},
-  prefix={a\space},
+  prefix={an\space},
+  prefixfirst={a\space},
   ]{mp}{MP}{Mana Point}
 
 \newacronym[