咬紧牙关

lit. to bite the teeth tightly (idiom); fig. to grit one's teeth and bear the pain / to bite the bullet

to bite / to nip

variant of 咬[yao3]

tight / strict / close at hand / near / urgent / tense / hard up / short of money / to tighten

tooth / ivory / CL:顆|颗[ke1]

jaw / mandibular joint

mountain pass / to close; to shut; to turn off / to confine; to lock (sb) up; to shut (sb in a room, a bird in a cage etc) / to concern; to involve