bolt—headed and externally threaded fastener designed to be assembled with a nut.
螺栓—设计连接螺母的有头和外螺纹的紧固件。
screw—mechanical fastener having basic design characteristics which facilitate its assembly into a tapped hole or to form its own threads during installation.
螺丝—机械紧固件基本设计为可以装配到一个已攻牙的孔里或其本身的牙攻入。

没想到自己会看不懂。

无量天尊，贫道是来看热闹的，看完热闹拿经验走人。