CROSIER, n. 1. A bishop crook or pastoral staff, a symbol of pastoral authority and care. It consists of a gold or silver staff, crooked at the top, and is carried occasionally before bishops and abbots, and held in the hand when they give solemn benedictions. The use of crosiers is ancient. Originally a crosier was a staff with a cross on the top, in form of a crutch or T. 2. In astronomy, four stars in the southern hemisphere, in the form of a cross.