A tailcoat is a man's formal jacket with a very unusual shape. In front it is short — it stops at the waist, and it does not close over the stomach. In back it hangs down in two long narrow pieces, almost to the back of the knees. Those two hanging pieces are the "tails", and that is where the name comes from. People wear it to the most formal events: a very grand wedding, a state dinner, a ball. Orchestra conductors and classical musicians often wear one on stage, and so do waiters in very old-style expensive restaurants. In real life, most people will never wear one. The everyday word is the plural: people say "in tails" or "white tie and tails" far more often than they say "tailcoat", which sounds like the word on the rental shop's list rather than the word a friend uses. The shape is also famous from cartoons and old films — the magician, the rich villain, the penguin — so even people who have never seen one in real life know the picture. Note that this jacket is not the same as a tuxedo (British: dinner jacket), which is shorter and has no tails; students often mix the two, and in English they belong to two different levels of formality, with tails being the higher one.

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