A long outer garment formerly worn by men and women, as well as by soldiers as part of their uniform. [1913 Webster]
A garment resembling a long frock coat worn by the clergy of certain churches when officiating, and by others as the usually outer garment. [1913 Webster]

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OXFORD DICTIONARY

cassock, n. a long close-fitting usu. black or red garment worn by clergy, members of choirs, etc.

Derivative

cassocked adj.

Etymology

F casaque long coat f. It. casacca horseman's coat, prob. f. Turkic: cf. COSSACK

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THESAURUS

cassock

churchman, cleric, clerical, clerk, confessor, cure, divine, ecclesiastic, father, father confessor, father in Christ, gallach, minister, padre, parish priest, parson, penitentiary, preacher, presbyter, priest, spiritual director, spiritual father

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ROGET THESAURUS

cassock

Canonicals

N canonicals, vestments, robe, gown, Geneva gown frock, pallium, surplice, cassock, dalmatic, scapulary, cope, mozetta, scarf, tunicle, chasuble, alb, alba, stole, fanon, fannel, tonsure, cowl, hood, calote, calotte, bands, capouch, amice, vagas, vakas, vakass, apron, lawn sleeves, pontificals, pall, miter, tiara, triple crown, shovel hat, cardinal's hat, biretta, crosier, pastoral staff, thurifer, costume.

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