Donkey punch

Donkey punch is a slang term for the sexual practice of inflicting blunt force trauma to the back of the head or lower back of the receiving partner during anal or vaginal sex as an attempt by the penetrating partner to induce involuntary tightening of internal or external anal sphincter muscles or vaginal passage of the receiving partner. According to Dr. Jeffrey Bahr of Medical College of Wisconsin there is no reflex in humans that would cause such tensing in response to a blow on the head, although striking a partner on the back of the neck or head could cause severe, even lethal injury.

To the best of my knowledge, there is no definitive reflex in the human neurophysiology that induces involuntary tightening of the anal sphincter after receiving blunt force trauma to the occiput, or back of the head. ... Trauma to any part of the head can have serious ramifications. Pain, intracranial hemorrhage, memory loss, neck injury, and possibly some related sensory deficits in the arms and legs. A strong enough blow to the back of an unsuspecting person's head could result in a vertebral fracture which, I hope most people know, could cause paralysis or even death.

Jordan Tate, commenting in The Contemporary Dictionary of Sexual Euphemisms (2007) on the "almost purely theoretical nature" of the term, claimed,

The donkey punch originated in the late twentieth century sometime after the sexual revolution, when the empowerment of women was threatening the place of men in contemporary society. This shift in gender paradigms left men feeling threatened, and to reassert their authority, they created and popularized these theoretical and violent euphemisms. ... The secondary reward of the donkey punch is the creation, or reinforcement, of the ideal power structure, or solidifying existing gender roles.

The concise new Partridge dictionary of slang and unconventional English (2007) defines the term as follows:

... during homosexual anal intercourse, a sharp blow given by the active partner to the passive partner's kidneys. The sudden pain from the blow causes a clenching of the buttocks and tightening of the rectal passage, thereby enhancing the pleasure of the penetrating participant. UK 2005

The adult film star credited as the first known recipient of a donkey punch is Gia Paloma, who had the act performed on her by Alex Sanders in the 2004 film Gutter Mouths 30.

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