anus

Pronunciation
/AY-nuhs/
Category
Anatomy
Singular
anus
Plural
anuses

Definition

The posterior opening of the digestive tract, used for the expulsion of waste material.

Etymology

From Latin 'ānus', meaning 'ring' or 'circle'.

Example

Certain beetles have an anus that allows them to expel defensive chemicals when threatened.

Synonyms

  • Anal opening
  • Rectal outlet

Related Terms

Usage Notes

In entomology and arachnology, the anus is typically a small, often musculature-controlled opening located at the end of the alimentary canal.