- a small opening allowing the outer air to come through into a confined space; air hole
- Geol. a small vent formed on the surface of a thick lava flow
- Zool. an aperture for breathing, as
- any of the small external openings of the tracheal respiratory system in most terrestrial arthropods, ordinarily along the sides of certain thoracic and abdominal segments; stigma
- any of various similar openings for the passage of air or respiratory water, as in tadpoles
- blowhole (sense )
Origin of spiracleMiddle English ; from Classical Latin spiraculum ; from spirare, to breathe: see spirit
- Zoology A respiratory aperture, especially:a. Any of several tracheal openings in the exoskeleton of an insect, spider, or other terrestrial arthropod.b. A small respiratory opening behind the eye of most sharks and rays and certain other fishes.c. The blowhole of a cetacean.
- An aperture or opening through which air is admitted and expelled.
Origin of spiracleMiddle English, from Latin sp&imacron;raculum, from sp&imacron;rare, to breathe.
Latin spiraculum, from spirare (“to breathe").