diff --git a/src/editorui/boxed/boxededitoruiview.js b/src/editorui/boxed/boxededitoruiview.js
index 40c79352..56c1065e 100644
--- a/src/editorui/boxed/boxededitoruiview.js
+++ b/src/editorui/boxed/boxededitoruiview.js
@@ -57,7 +57,7 @@ export default class BoxedEditorUIView extends EditorUIView {
 				],
 				role: 'application',
 				dir: 'ltr',
-				lang: locale.lang,
+				lang: locale.language,
 				'aria-labelledby': `cke-editor__aria-label_${ ariaLabelUid }`
 			},