| 释义 |
spi·ra·cle
\ˈspirəkəl, -pīr-\ noun
(-s)
Etymology: in sense 1, from Middle English, from Late Latin spiraculum, from Latin, air hole, spiracle, from spirare to breathe; in other senses, from Latin spiraculum — more at spirit
1. obsolete : breath, spirit
2.
a. : a usually small aperture giving a confined space communication with the outer air : a breathing hole : air hole, vent
b. : a steam or gas vent on the surface of a lava flow
3. : a breathing orifice
a. : the blowhole of a cetacean
b. : an external tracheal aperture of a terrestrial arthropod that in an insect is usually one of a series of small more or less elliptical apertures often having a valve and a protective sievelike structure or fringe of hairs and being located along each side of the thorax and abdomen usually in 10 pairs but sometimes 11 or occasionally fewer — see insect illustration
c. : one of the orifices or passages that open on the upper back part of the head of many elasmobranchs and some higher fishes (as a sturgeon or the bichir), communicate with the mouth cavity, represent the first postoral visceral clefts of the embryo, in rays serve instead of the mouth as a chief incurrent respiratory openings, and may contain a rudimentary gill
d. : the excurrent aperture of the gill chamber of a tadpole developing from two apertures that unite in a canal which opens on the left side of the body or rarely on the middle of the undersurface |