A man's anus, in a sexual context.
A hole in the ground used to access the sewers or other underground vaults and installations.
A hole providing access to the inside of a boiler, tank etc.
An artificial anus.
One of the tiny pores in the epidermis of a leaf or stem through which gases and water vapor pass.
A small opening in a membrane; a surgically constructed opening, especially one in the abdominal wall that permits the passage of waste after a colostomy or ileostomy.
A mouthlike opening, such as the oral cavity of a nematode.