n.
Pronunciation: ' spir-i-k ə l, ' sp ī -ri-
Function: noun
Etymology: Middle English, from Latin spiraculum, from spirare to breathe
Date: 15th century
1 : a breathing hole : VENT
2 : a breathing orifice: as a : BLOWHOLE 2 b : an external tracheal aperture of a terrestrial arthropod that in an insect is usually one of a series of small apertures located along each side of the thorax and abdomen ― see INSECT illustration
– spi · rac · u · lar \ sp ə - ' ra-ky ə -l ə r, sp ī - \ adjective