tailcoat

n. man's formal evening coat with a short front and long and tapering in the back

A tailcoat, sometimes a swallow-tail coat is the coat traditionally worn by men for white tie dress, for very formal evening occasions.A tailcoat is waist length in the front and sides, and has two long tails reaching to the knees in back. (Sometimes with a pocket on the inside meant to hold gloves). In this respect the tailcoat is a modification of the older frock coat: the frock coat goes down to the knees all the way around, and lower edge of its other descendant, the morning coat or cutaway, slants diagonally from the waist in front to the knees in back, the tailcoat is cut away more dramatically across.
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Noun
1. formalwear consisting of full evening dress for men
(synonym) dress suit, full dress, tail coat, tails, white tie, white tie and tails
(hypernym) formalwear, eveningwear, evening dress, evening clothes
(part-meronym) swallow-tailed coat, swallowtail, morning coat

    coattail

MARSINA. FRAC