a breathing hole; an opening by which
a confined space has communication with the outer air; air hole.
2. Zoology. a.
or orifice through which air or water passes in the act of respiration, as the blowhole of a cetacean.
an opening in the head of sharks and rays through which water is drawn and passed over gills.
one of the external orifices of the tracheal respiratory system
of certain invertebrates, usually on the sides of the body. See diag. under insect
Origin: 1300–50; Middle English Related forms
< Latin spīrāculum
air hole, equivalent to spīrā
) to breathe + -culum -cle2
spiracular /spaɪˈrækyələr, spɪ-/ [spahy-rak-yuh-ler, spi-] Show IPA , adjective