One who performs feats of rolling, somersaulting, or the like, as on mats; an acrobat.

翻滚者；翻筋斗者；杂耍演员。

A drinking glass with straight sides, but without a stem.

(无柄、无脚之)平底玻璃杯。

A part of a lock that must be put in a certain position, generally by the key, before the bolt can be moved.

(锁中之)制栓(必须有钥匙与其特别之位置相合，方可将栓脱出)。

A kind of pigeon which, when flying, turns somersaults in the air.

翻飞鸽(=tumbler pigeon)。

Self-righting toy.

不倒翁。