A shepherd's crook is a long and sturdy stick with a hook at one end, often with the point flared outwards, used by a shepherd to manage and sometimes catch sheep. In addition, the crook may aid in defending against attack by predators. When traversing rough terrain, a crook is an aid to balance. Shepherds may also use the long implement to part thick undergrowth (for example at the edge of a drovers' road) when searching for lost sheep or potential predators.
The innovation of a hook facilitates the recovery of fallen animals by ensnaring them by the neck or leg. For this reason the crook has been used as a religious symbol of care (particularly in difficult circumstances), including the Christian bishop's crosier.
In medicine, the term shepherd’s crook is used to describe a right coronary artery that follows an unusually high and winding route. This variant, which has a prevalence of about 5%, imposes technical problems in angioplasty procedures.
The shepherd's crook and the flail (an agricultural tool) are insignia of pharaonic authority