• Webster's Revised Unabridged Dictionary
    • a Spiracular Of or pertaining to a spiracle.
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Century Dictionary and Cyclopedia
    • spiracular Of or pertaining to a spiracle, breathing-hole, or blow-hole.
    • spiracular Fitted for or permitting respiration, as a spiracle; respiratory.
    • n spiracular A small bone or cartilage in special relation with the spiracle of some fishes.
    • ***


In literature:

Spiracular sulcus: on the metanotum of Hymenoptera, is a grooved linear channel extending from spiracle to apical margin.
"Explanation of Terms Used in Entomology" by John. B. Smith
It is pointed at the head end and blunt at the opposite end, where the spiracular openings are borne.
"Handbook of Medical Entomology" by William Albert Riley