A shiv, also chiv, schiv, shivvie or shank,[1][2] is a handcrafted bladed weapon resembling a knife that is commonly associated with prison inmates.
Routine body searches in prison make it difficult to conceal a shiv on one's person on a continuous basis.
[3][4] The derived verb shiv means "to stab someone", and a shivver is an archaic term for a criminal who attacks victims with a knife.
In the 1950s, British criminal Billy Hill described his use of the shiv: I was always careful to draw my knife down on the face, never across or upwards.
[6]In the Federal Bureau of Prisons, weapons, sharpened instruments, and knives are considered contraband and their possession is punishable as a highest severity-level prohibited act.