4.to open sth a crack把某物微微打开一点
He went to the door, opened it a crack, and listened.他走到门边, 把门打开一条缝, 然后侧耳倾听。
5.(noise; of branches, wood, glass, gun)爆裂声；噼啪声
(of thunder)霹雳声
Suddenly there was a loud crack and glass flew into the car.突然啪的一声巨响, 玻璃飞进了汽车内。
6.<非正式>(joke)挖苦话；俏皮话；笑话
There were cracks about the Prime Minister.对首相有一些挖苦。
7.<非正式>(attempt)尝试
8.<俚>(crack cocaine)强效纯可卡因
9.(blow)啪的一击
10.(tone of voice)(嗓子的)发哑, 变声
He was ashamed of the crack in his voice.他对自己的变声感到难为情。
11.<非正式>(fun)玩乐；娱乐
12.<苏格兰,英格兰北部,方>(chat)谈话；聊天
13.at the crack of dawn
(very early)一大早；大清早
I often start work at the crack of dawn.我经常一大早就开始工作。
(the minute the sun rises)在破晓时；在黎明时