Ber*ret"ta (?), n. [It., fr. LL.
birrettum, berretum, a cap, dim. of L. birrus,
birrum, a cloak to keep off rain, cf. Gr. ? tawny, red: cf.
Sp. birreta, Pg. barrete, and E. Barret.] A
square cap worn by ecclesiastics of the Roman Catholic Church. A cardinal's
berretta is scarlet; that worn by other clerics is black, except that a
bishop's is lined with green. [Also spelt beretta,
biretta, etc.]