diff --git a/wp-includes/taxonomy.php b/wp-includes/taxonomy.php
index 9a3a13cb29..1c63b9be03 100644
--- a/wp-includes/taxonomy.php
+++ b/wp-includes/taxonomy.php
@@ -2063,7 +2063,7 @@ function wp_insert_term( $term, $taxonomy, $args = array() ) {
 				$siblings = get_terms( $taxonomy, array( 'get' => 'all', 'parent' => $parent ) );
 
 				$existing_term = null;
-				if ( $name_match->slug === $slug && in_array( $name, wp_list_pluck( $siblings, 'name' ) ) ) {
+				if ( ( ! $slug_provided || $name_match->slug === $slug ) && in_array( $name, wp_list_pluck( $siblings, 'name' ) ) ) {
 					$existing_term = $name_match;
 				} elseif ( $slug_match && in_array( $slug, wp_list_pluck( $siblings, 'slug' ) ) ) {
 					$existing_term = $slug_match;
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 13234d83a8..45e2331232 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-40143';
+$wp_version = '4.8-alpha-40144';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.