Cognomen 瓦伊 (瓦伊 
, Vahey 
) , in the world, is quite a rare surname. The last name 瓦伊 is habitual in Ireland, where it is quite a rare surname, Israel, where it is a rare surname, and Canada. In absolute terms, it is commonest in the United States, Ireland, and the United Kingdom. Very seldom, 瓦伊 is the forename as well as the last name.