1. The bottom side of a coin, especially when tossed into the air to determine an outcome. If it's heads, I'll do the dishes, but if it's tails, then you have to do them. "Tails!" he shouted as Sarah tossed the coin in the air.

2. A formal coat with long, split ends at the back. When were seated by a maître d' was wearing tails, I knew we were in for a very fancy meal. I need to get my tails dry cleaned for the gala next Tuesday.