1. In basketball, a situation in which the player awarded free throws (foul shots) is given one shot. If the player makes the first shot, they are awarded a second shot; if they miss the first shot, the ball is in play and they are not awarded a second shot. Often hyphenated. The next time we foul, it will be a one-and-one, so don't foul unless you have to.

2. slang The inhalation of powdered drugs through the nostrils, especially cocaine. I mostly just smoke weed, though I do a little one and one every now and then if someone's brought something to a party.