See buckle in Webster's New World Roget's A-Z Thesaurus II
verb
To fall in:
cave in, collapse, crumple, give, go. Idiom: give way. See explosionTo give in from or as if from a gradual loss of strength:
bow1, capitulate, submit, succumb, surrender, yield. (Informal) fold. See resist
phrasal verb buckle downTo devote (oneself or one's efforts):
address, apply, bend, concentrate, dedicate, devote, direct, focus, give, turn. See collect, work
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