[spi.ra.cle] n [ME, fr. L spiraculum, fr. spirare to breathe] (15c) 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 usu. one of a series of small apertures located along each side of the thorax and abdomen--see insect illustration -- spi.rac.u.lar adj