diff --git a/src/window.cpp b/src/window.cpp
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -655,7 +655,7 @@ static void DispatchLeftClickEvent(Windo
 
 	/* Clicked on a widget that is not disabled.
 	 * So unless the clicked widget is the caption bar, change focus to this widget.
-	 * Exception: In the OSK we always want the editbox to stay focussed. */
+	 * Exception: In the OSK we always want the editbox to stay focused. */
 	if (widget_type != WWT_CAPTION && w->window_class != WC_OSK) {
 		/* focused_widget_changed is 'now' only true if the window this widget
 		 * is in gained focus. In that case it must remain true, also if the