The halyawhai is a short, stout heavy mesquite war club of the Mohave people of the southwestern United States. It is one of a class of weapons known as "potato-masher" clubs.

The striking surface is comprised of a thick, cylindrical mallet-like head, with some examples having a burned-in hollow at the top featuring a sharp carved edge. Usual form was to bring the club head up towards the chin or face, rather than clubbing downward.

Unlike the similar clubs of neighboring peoples, the handle was not sharpened to form a stabbing surface.