diff --git a/blns.json b/blns.json
index 51ac199..4c4d078 100644
--- a/blns.json
+++ b/blns.json
@@ -1,6 +1,7 @@
 [
   "", 
   "undefined", 
+  "undef",
   "null", 
   "NULL", 
   "nil", 
diff --git a/blns.txt b/blns.txt
index d52abc5..b9b7a24 100644
Binary files a/blns.txt and b/blns.txt differ