Dictionary > Orifice

Orifice

Definition
noun, plural: orifices
An opening or aperture; any external opening in the body of an animal.
Supplement
In a typical mammalian body such as the human body, the body orifices are: nostrils, eyes, mouth, ear canals, anus, urethra, vagina, orifices of nipples, orifices of sweat glands, navel.
Other animals may have some other body orifices: cloaca in birds, reptiles, amphibians, and some other animals, and siphon in mollusca, arthropods, and some other animals.
Word origin: Middle English, from Old French, from Late Latin orificium, compound of os, mouth + -ficium.
Related forms: orificial (adjective).

Related terms:

  • anal orifice
  • aortic orifice
  • cardiac orifice
  • orifice of external acoustic meatus
  • orifice of inferior vena cava
  • tricuspid orifice
  • vaginal orifice


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