(1):

(n.) A close cap without visor or brim.

(2):

(n.) Such a cap, worn by English serjeants at law.

(3):

(n.) Such a cap, worn by the clergy of the Roman Catholic Church.

(4):

(n.) Such a cap, worn by the French cavalry under their helmets.

(5):

(n.) A plant coif or skullcap. Same as Calotte.