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
2. Also called: swallow-tailed coat. another name for morning coat
tail coat in American English
noun
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: tailcoat. Also called: tails, dress coat, swallow-tailed coat
Word origin
[1840–50]This word is first recorded in the period 1840–50. Other words that entered Englishat around the same time include: bypass, colloid, pylon, sensationalism, set piece