Decapitation

Decapitation (from Latin, caput, capitis, meaning head) is the separation of the head from the body. It is impossible for a human to survive such an injury, since severing the head deprives all other organs of the involuntary functions that are essential for the body to function while the brain itself is deprived of oxygenated blood.

Beheading typically refers to the act of intentional decapitation, either as a means of murder or execution; it may be accomplished, for example, with an axe, sword, knife, or by other more sophisticated means such as a guillotine. An executioner carrying out decapitations is called a headsman. Accidental decapitation can be the result of an explosion, car or industrial accident, improperly administered execution by hanging or other violent injury. Suicide by decapitation is rare, but not unknown. The national laws of Saudi Arabia, Yemen, Iran, and Qatar permit beheading, but in practice, Saudi Arabia is the only country that continues to behead its offenders regularly as a punishment for crime.

Less commonly, decapitation can also refer to the removal of the head from a body that is already dead. This might be done to take the head as a trophy, for public display, to make the deceased more difficult to identify, for cryonics, or for other, more esoteric reasons.

https://en.wikipedia.org/wiki/Decapitation