diff --git a/lib/binding_web/binding.js b/lib/binding_web/binding.js
index 7af8a92c..766abd54 100644
--- a/lib/binding_web/binding.js
+++ b/lib/binding_web/binding.js
@@ -642,7 +642,7 @@ class Language {
   }
 
   fieldNameForId(fieldId) {
-    return this.fields[fieldName] || null;
+    return this.fields[fieldId] || null;
   }
 
   query(source) {