to move your tongue over your lips, especially before eating sth good
lick / smack your lips
to move your tongue over your lips, especially before eating sth good
lick / smack your lipsinformal
to show that you are excited about sth and want it to happen soon
They were licking their lips at the thought of clinching the deal.
Definiciones del Oxford Advanced Learner's Dictionary, 9.ª edición