noun
- 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:
ME < L spiraculum < spirare, to breathe: see spirit