A body orifice is any opening in the body of an organism.
External In a typical mammalian body such as the human body, the external body orifices are:
The nostrils, for breathing and the associated sense of smell The mouth, for eating, drinking, breathing, and vocalizations such as speech The ear canals, for the sense of hearing The nasolacrimal ducts, to carry tears from the lacrimal sac into the nasal cavity The anus, for defecation The urinary meatus, for urination, male ejaculation, and female ejaculation In females, the vagina, for menstruation, copulation and birth The nipple orifices
Other animals may have some other body orifices: cloaca, in birds, reptiles, amphibians, and a few mammals, such as monotremes siphon in mollusks, arthropods, and some other animals
Internal Internal orifices include the orifices of the outflow tracts of the heart between the heart valves.
See also Internal urethral orifice Mucosa Mucocutaneous boundary Meatus Body cavity
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