diff --git a/monster/animal/giant_worm/purple_worm.arc b/monster/animal/giant_worm/purple_worm.arc
index ed9484967..5443ef438 100644
--- a/monster/animal/giant_worm/purple_worm.arc
+++ b/monster/animal/giant_worm/purple_worm.arc
@@ -11,7 +11,7 @@ Wis 20
 Dex 15
 Con 30
 Int 10
-armour 85
+resist_physical 85
 resist_magic 30
 resist_acid 100
 resist_fire 30