diff --git a/Lib/csharp/swiginterface.i b/Lib/csharp/swiginterface.i
index 245ab7f7a..3741b87ac 100644
--- a/Lib/csharp/swiginterface.i
+++ b/Lib/csharp/swiginterface.i
@@ -55,8 +55,8 @@ INTERFACE_TYPEMAPS(CTYPE)
 INTERFACE_TYPEMAPS(CTYPE)
 %enddef
 
-%define %interface_custom(IMPL, INTERFACE, CTYPE...)
-%rename(IMPL) CTYPE;
+%define %interface_custom(PROXY, INTERFACE, CTYPE...)
+%rename(PROXY) CTYPE;
 %feature("interface", name=INTERFACE) CTYPE;
 INTERFACE_TYPEMAPS(CTYPE)
 %enddef
diff --git a/Lib/java/swiginterface.i b/Lib/java/swiginterface.i
index 52979ad78..169118278 100644
--- a/Lib/java/swiginterface.i
+++ b/Lib/java/swiginterface.i
@@ -66,8 +66,8 @@ INTERFACE_TYPEMAPS(CTYPE)
 INTERFACE_TYPEMAPS(CTYPE)
 %enddef
 
-%define %interface_custom(IMPL, INTERFACE, CTYPE...)
-%rename(IMPL) CTYPE;
+%define %interface_custom(PROXY, INTERFACE, CTYPE...)
+%rename(PROXY) CTYPE;
 %feature("interface", name=INTERFACE) CTYPE;
 INTERFACE_TYPEMAPS(CTYPE)
 %enddef