noun · a backward-pointing projection on a hook, arrow, or similar object

这种鱼钩带有倒钩，一旦钩住就很不容易脱落。

verb · a football (soccer) maneuver where a player kicks the ball backward over their head while in mid-air

他在比赛最后三分钟完成了一个精彩的倒钩射门。