A head on a spike (also described as a head on a pike, a head on a stake, or a head on a spear) is a severed head that has been vertically impaled for display. This has been a custom in a number of cultures, typically either as part of a criminal penalty following execution or as a war trophy following a violent conflict. The symbolic value may change over time. It may give a warning to spectators. The head may be a human head or an animal head.