diff --git a/src/wp-includes/taxonomy.php b/src/wp-includes/taxonomy.php
index 5936fb3d1f..2fdc62a2a6 100644
--- a/src/wp-includes/taxonomy.php
+++ b/src/wp-includes/taxonomy.php
@@ -4125,11 +4125,12 @@ function _split_shared_term( $term_id, $term_taxonomy_id ) {
 	 *
 	 * @since 4.1.0
 	 *
-	 * @param int $term_id          ID of the formerly shared term.
-	 * @param int $new_term_id      ID of the new term created for the $term_taxonomy_id.
-	 * @param int $term_taxonomy_id ID for the term_taxonomy row affected by the split.
+	 * @param int    $term_id          ID of the formerly shared term.
+	 * @param int    $new_term_id      ID of the new term created for the $term_taxonomy_id.
+	 * @param int    $term_taxonomy_id ID for the term_taxonomy row affected by the split.
+	 * @param string $taxonomy         Taxonomy for the split term.
 	 */
-	do_action( 'split_shared_term', $term_id, $new_term_id, $term_taxonomy_id );
+	do_action( 'split_shared_term', $term_id, $new_term_id, $term_taxonomy_id, $term_taxonomy->taxonomy );
 
 	return $new_term_id;
 }