diff --git a/components/serializer.rst b/components/serializer.rst
index f4f1a7ca123..aa0c3fd8c08 100644
--- a/components/serializer.rst
+++ b/components/serializer.rst
@@ -639,7 +639,7 @@ When serializing, you can set a callback to format a specific object property::
     $encoder = new JsonEncoder();
 
     // all callback parameters are optional (you can omit the ones you don't use)
-    $dateCallback = function ($innerObject, $outerObject, string $attributeName, string $format = null, array $context = []) {
+    $callback = function ($innerObject, $outerObject, string $attributeName, string $format = null, array $context = []) {
         return $innerObject instanceof \DateTime ? $innerObject->format(\DateTime::ISO8601) : '';
     };