diff --git a/src/lua_mathlib.c b/src/lua_mathlib.c
index 9a288e17b..45168ad79 100644
--- a/src/lua_mathlib.c
+++ b/src/lua_mathlib.c
@@ -87,7 +87,7 @@ static int lib_finetangent(lua_State *L)
 	return 1;
 }
 
-static int lib_finearccosine(lua_State *L)
+static int lib_fixedacos(lua_State *L)
 {
 	lua_pushangle(L, FixedAcos(luaL_checkfixed(L, 1)));
 	return 1;
@@ -198,7 +198,7 @@ static luaL_Reg lib[] = {
 	{"sin", lib_finesine},
 	{"cos", lib_finecosine},
 	{"tan", lib_finetangent},
-	{"acos", lib_finearccosine},
+	{"acos", lib_fixedacos},
 	{"FixedAngle", lib_fixedangle},
 	{"fixangle"  , lib_fixedangle},
 	{"AngleFixed", lib_anglefixed},