tailcoat

UK: /ˈteɪlkəʊt/

WordReference Random House Learner's Dictionary of American English © 2025

ˈtail ˌcoat or ˈtailˌcoat, n. [countable]

1. Clothing a man's formal coat, with a pair of long pieces behind.

Also called tails. 

WordReference Random House Unabridged Dictionary of American English © 2025

tail′ coat′. 

1. Clothing a man's fitted coat, cut away over the hips and descending in a pair of tapering skirts behind, usually black and worn as part of full evening dress.

Also, tail′coat′. Also called tails, dress coat, swallow-tailed coat. 

• 1840–50

Collins Concise English Dictionary © HarperCollins Publishers::

tail coat, tailcoat / ˈteɪlˌkəʊt/ noun

1. Also called: tails a man's black coat having a horizontal cut over the hips and a tapering tail with a vertical slit up to the waist: worn as part of full evening dress