Branchial (&unr_;), a. (Anat.) Of or pertaining to branchiæ or gills.
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Branchial arches, the bony or cartilaginous arches which support the gills on each side of the throat of fishes and amphibians. See Illustration in Appendix. -- Branchial clefts, the openings between the branchial arches through which water passes.
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