Noun | 1. | ![]() lip - either of two fleshy folds of tissue that surround the mouth and play a role in speaking arteria, arterial blood vessel, artery - a blood vessel that carries blood from the heart to the body arteria labialis inferior, inferior labial artery - an artery that is a branch of the facial artery that supplies the lower lip arteria labialis superior, superior labial artery - an artery that is a branch of the facial artery that supplies the upper lip |