Turkey slap is a sexual behaviour in which a male slaps another person's face with his penis

Penis

The penis is a biological feature of male animals including both vertebrates and invertebrates...

 (the "turkey"). While the act of hitting another's face with the penis can be a sexual act, the term "turkey slap" refers to the act when performed in a non-sexual way either playfully or to shame, degrade or harass the victim. The turkey slap draws its name from the resemblance of the male's scrotum

Scrotum

In some male mammals the scrotum is a dual-chambered protuberance of skin and muscle containing the testicles and divided by a septum. It is an extension of the perineum, and is located between the penis and anus. In humans and some other mammals, the base of the scrotum becomes covered with curly...

 to the wattle under a turkey

Turkey (bird)

A turkey is a large bird in the genus Meleagris. One species, Meleagris gallopavo, commonly known as the Wild Turkey, is native to the forests of North America. The domestic turkey is a descendant of this species...

's neck.

The term gained notoriety in Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 during 2006, after two male contestants in the Big Brother reality TV series performed the act on a female housemate. In the ensuing controversy, the male housemates were expelled from the house and contest for violating the show's terms of agreement.