tailcoat(n = noun.artifact) dress suit, full dress, tail coat, tails, white tie, white tie and tails - formalwear consisting of full evening dress for men;
is a kind of evening clothes, evening dress, eveningwear, formalwear
has parts: morning coat, swallow-tailed coat, swallowtail

tailcoat, n. a man's morning or evening coat with a long skirt divided at the back into tails and cut away in front, worn as part of formal dress.