1
- a flat, typically rectangular or oval frame with a hinged pin, used for joining the ends of a belt or strap带扣; 皮带等的搭扣, 搭钩。
1.1
- a similarly shaped ornament, especially on a shoe（尤指鞋的）扣形饰物。
1
- with obj. fasten or decorate with a buckle扣住; 用搭扣装饰：
he buckled his belt.
他扣上了他的皮带。
1.1
- no obj.
buckle up
fasten one's seat belt in a car or aircraft系上安全带。
2
- no obj. bend and give way under pressure or strain屈服; 退让; 投降：
the earth buckled under the titanic stress.
在巨大的压力下, 地面下陷了。
ORIGIN: from French boucler 'to bulge'.
2.1
- with obj. bend (something) out of shape使弯曲变形：
a lorry backed into the wall and buckled the gate.
一辆卡车倒车时撞到了墙上, 把门撞得变了形。
2.2
- figurative (of a person) suffer a psychological collapse as a result of enormous stress or pressure〈喻〉（人）精神崩溃：
a weaker person might have buckled under the strain.
一个软弱一点的人在这样的压力下可能就垮了。
词源
Middle English: from Old French bocle, from Latin buccula 'cheek strap of a helmet'， from bucca 'cheek'.
短语动词
buckle down
- tackle a task with determination倾注全力, 认真干：
they will buckle down to negotiations over the next few months.
接下来的几个月他们将认真开始谈判。
buckle to
- dated make a determined effort〈旧〉努力干起来。