diff --git a/vscode/syntaxes/toit.tmLanguage.json b/vscode/syntaxes/toit.tmLanguage.json
index 41e65ce..50bc786 100644
--- a/vscode/syntaxes/toit.tmLanguage.json
+++ b/vscode/syntaxes/toit.tmLanguage.json
@@ -745,7 +745,7 @@
         },
         {
           "name": "entity.name.type.toit",
-          "match": "\\b(?<!-)_?[A-Z][0-9]*(?<!-)\\b[?]?"
+          "match": "\\b(?<!-)_?[A-Z][0-9]*_?(?<!-)\\b[?]?"
         },
         {
           "name": "entity.name.type.shorts.toit",
diff --git a/vscode/syntaxes/toit.tmLanguage.yaml b/vscode/syntaxes/toit.tmLanguage.yaml
index b342f58..d57138e 100644
--- a/vscode/syntaxes/toit.tmLanguage.yaml
+++ b/vscode/syntaxes/toit.tmLanguage.yaml
@@ -464,7 +464,7 @@ repository:
     - name: entity.name.type.toit
       match: \b(?<!-)_?[A-Z][A-Z_-]*[a-z][\w-]*(?<!-)\b[?]?
     - name: entity.name.type.toit
-      match: \b(?<!-)_?[A-Z][0-9]*(?<!-)\b[?]?
+      match: \b(?<!-)_?[A-Z][0-9]*_?(?<!-)\b[?]?
     - name: entity.name.type.shorts.toit
       match: \b(?<!-)(int|bool|float|string)(?<!-)\b[?]?
     - name: entity.name.type.any_none.toit