diff --git a/src/Github/Api/V3/CreateMilestoneThroughApiCall.php b/src/Github/Api/V3/CreateMilestoneThroughApiCall.php
index e4de0400..a8f7e378 100644
--- a/src/Github/Api/V3/CreateMilestoneThroughApiCall.php
+++ b/src/Github/Api/V3/CreateMilestoneThroughApiCall.php
@@ -82,7 +82,7 @@ public function __invoke(RepositoryName $repository, SemVerVersion $version): vo
     private function milestoneDescription(SemVerVersion $version): string
     {
         if ($version->isNewMajorRelease()) {
-            return 'Backwards incompatible release (major)';
+            return 'Backward incompatible release (major)';
         }
 
         if ($version->isNewMinorRelease()) {
diff --git a/test/unit/Github/Api/V3/CreateMilestoneTest.php b/test/unit/Github/Api/V3/CreateMilestoneTest.php
index d045a363..2736d146 100644
--- a/test/unit/Github/Api/V3/CreateMilestoneTest.php
+++ b/test/unit/Github/Api/V3/CreateMilestoneTest.php
@@ -190,7 +190,7 @@ public function testMajorMilestone(): void
                 self::assertJsonStringEqualsJsonString(
                     <<<'JSON'
                     {
-                        "description": "Backwards incompatible release (major)",
+                        "description": "Backward incompatible release (major)",
                         "title": "3.0.0"
                     }
                     JSON,