diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5edf407..58dd571 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,11 @@
 
 All notable changes to the **Bison/Flex Language Support** extension will be documented in this file.
 
-## [1.5.2] - 2026-04-03
+## [1.5.2] - 2026-04-05
+
+### Added
+
+- **Flex — Code Lens for abbreviations** (#39): abbreviation definitions in the definitions section now show a clickable "N references" Code Lens, consistent with start conditions and Bison rules. Clicking opens the References panel with all `{ABBR}` usages in the rules section.
 
 ### Fixed
 
diff --git a/server/src/providers/codeLens.ts b/server/src/providers/codeLens.ts
index b1b2ed8..f6601b4 100644
--- a/server/src/providers/codeLens.ts
+++ b/server/src/providers/codeLens.ts
@@ -3,8 +3,9 @@ import { DocumentModel, BisonDocument, FlexDocument, isBisonDocument } from '../
 
 /**
  * Code Lenses:
- *   Bison rules   → "N references"  +  "⬤ entry point" (start symbol only)
- *   Flex SC decls → "N references"
+ *   Bison rules        → "N references"  +  "⬤ entry point" (start symbol only)
+ *   Flex SC decls      → "N references"
+ *   Flex abbreviations → "N references"
  *
  * The "N references" lens triggers `bisonFlex.showReferences` (registered
  * client-side) which calls `editor.action.showReferences` with pre-built args.
@@ -71,5 +72,21 @@ function getFlexCodeLenses(doc: FlexDocument, uri: string): CodeLens[] {
     });
   }
 
+  for (const [name, abbr] of doc.abbreviations) {
+    const line = abbr.location.start.line;
+    const lensRange = Range.create(line, 0, line, 0);
+    const refCount = doc.abbreviationRefs.get(name)?.length ?? 0;
+
+    lenses.push({
+      range: lensRange,
+      command: Command.create(
+        `$(references) ${refCount} reference${refCount !== 1 ? 's' : ''}`,
+        'bisonFlex.showReferences',
+        uri,
+        { line, character: abbr.location.start.character },
+      ),
+    });
+  }
+
   return lenses;
 }
diff --git a/tests/test-diagnostic-codes.ts b/tests/test-diagnostic-codes.ts
index 7830645..111cdfc 100644
--- a/tests/test-diagnostic-codes.ts
+++ b/tests/test-diagnostic-codes.ts
@@ -622,6 +622,35 @@ console.log('\n=== TEST: isWordPattern — complex patterns do not shadow keywor
   assert(unreachable.length >= 1, 'isWordPattern: simple [A-Z_]+ still shadows keyword "IF" → flex/unreachable-rule expected');
 }
 
+// ─────────────────────────────────────────────────────────────────────────────
+// Issue #39 — Code Lens for abbreviations
+// ─────────────────────────────────────────────────────────────────────────────
+console.log('\n=== TEST: Issue #39 — Code Lens for abbreviations ===');
+
+{
+  const { getCodeLenses } = require('../server/src/providers/codeLens');
+  const src = [
+    '%option noyywrap',
+    'DIGIT  [0-9]+',
+    'WORD   [a-z]+',
+    '%%',
+    '{DIGIT}  { return 1; }',
+    '{DIGIT}  { return 2; }',
+    '%%',
+  ].join('\n');
+  const doc = require('../server/src/parser/flexParser').parseFlexDocument(src);
+  const lenses = getCodeLenses(doc, 'file:///test.l');
+
+  // DIGIT is on line 1, WORD on line 2
+  const digitLens = lenses.find((l: any) => l.range.start.line === 1);
+  const wordLens  = lenses.find((l: any) => l.range.start.line === 2);
+
+  assert(!!digitLens, '#39: Code Lens produced for DIGIT abbreviation');
+  assert(digitLens?.command?.title?.includes('2'), '#39: DIGIT lens shows 2 references (used twice in rules)');
+  assert(!!wordLens,  '#39: Code Lens produced for WORD abbreviation');
+  assert(wordLens?.command?.title?.includes('0'), '#39: WORD lens shows 0 references (unused)');
+}
+
 // ─────────────────────────────────────────────────────────────────────────────
 // Bison audit checks
 // ─────────────────────────────────────────────────────────────────────────────