Orderride view in yii2

Hi all, can you please advise the way to pass a variable to theme in Yii2.x.

Like Yii::$app->view->title, I want to create and use Yii::$app->view->metaTitle for title of page. Actually I am using Yii::$app->view->title in template for h1 heading. Need to create new var for page title.

Please advise.