diff --git a/src/scripting/thingdef_data.cpp b/src/scripting/thingdef_data.cpp
index 5a0f2b3c98c..be1436d2298 100644
--- a/src/scripting/thingdef_data.cpp
+++ b/src/scripting/thingdef_data.cpp
@@ -1272,7 +1272,7 @@ DEFINE_ACTION_FUNCTION(FStringStruct, LastIndexOf)
 	ACTION_RETURN_INT(self->LastIndexOf(substr, endIndex));
 }
 
-DEFINE_ACTION_FUNCTION(FStringStruct, RIndexOf)
+DEFINE_ACTION_FUNCTION(FStringStruct, RightIndexOf)
 {
 	PARAM_SELF_STRUCT_PROLOGUE(FString);
 	PARAM_STRING(substr);
diff --git a/wadsrc/static/zscript/base.txt b/wadsrc/static/zscript/base.txt
index 4bf64e96662..8da0854ad7b 100644
--- a/wadsrc/static/zscript/base.txt
+++ b/wadsrc/static/zscript/base.txt
@@ -815,7 +815,7 @@ struct StringStruct native
 	native String Filter();
 	native int IndexOf(String substr, int startIndex = 0) const;
 	deprecated("3.5") native int LastIndexOf(String substr, int endIndex = 2147483647) const;
-	native int RIndexOf(String substr, int endIndex = 2147483647) const;
+	native int RightIndexOf(String substr, int endIndex = 2147483647) const;
 	native void ToUpper();
 	native void ToLower();
 	native int ToInt(int base = 0) const;