Bit your lip - Idioms by The Free Dictionary
bite (one's) lip (redirected from bit your lip)
bite (one's) lip
To forcibly prevent oneself from exhibiting an outward reaction to something, especially that which makes one angry, irritated, or upset. I just had to bite my lip while the boss yelled at me for losing the account. If someone tries to provoke you, just bite your lip and keep walking.
bite your lip repress an emotion; stifle laughter or a retort.
bite your ˈlip force yourself not to express the negative emotions that you are feeling: You could tell she thought the criticism was unfair but she bit her lip and said nothing. OPPOSITE: let rip (at somebody) (with something)