nipple

Universal Words noun 1 either of the two small round dark parts on a person's chest. Babies can suck milk from their mother's breasts through the nipples. 2 (AmE) = TEAT(1) 3 a small metal, plastic or rubber object that is shaped like a nipple with a small hole in the end, especially one that is used as part of a machine to direct oil, etc. into a particular place: a grease nipple