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


You will also like...

Lake Wakatipu, New Zealand
New Zealand’s Unique Geographical History

Explore why New Zealand has such unique flora and fauna, and learn why long periods of geographical isolation. This less..

dinosaurs
The Dinosaurs

Dinosaurs represented a major turn in the evolutionary development of organisms on Earth. The first dinosaurs were presu..

DNA - schematic
Genetic Mutations

This tutorial looks at the mutation at the gene level and the harm it may bring. Learn about single nucleotide polymorph..

Transpiration
Water in Plants

The movement of molecules (specifically, water and solutes) is vital to the understanding of plant processes. This tuto..

"Opabinia regalis"
The Evolutionary Development of Multicellular Organisms

Multicellular organisms evolved. The first ones were likely in the form of sponges. Multicellularity led to the evolutio..

Early Mammals on Earth
Early Mammals on Earth

The Earth's ecosphere was rapidly changing and throwing up a wide range of ecological niches that new adaptive organisms..

Related Articles...

No related articles found

See all Related Topics