Zoology. one of a series of bony or cartilaginous arches on each side of the pharynx that support the gills of fishes and aquatic amphibians; gill bar.
Embryology. one of a series of archlike mesodermal thickenings of the body wall in the pharyngeal region of the embryo of amphibians, reptiles, birds, and mammals.
Zoology. one of a series of slitlike openings in the walls of the pharynx between the branchial arches of fishes and aquatic amphibians through which water passes from the pharynx to the exterior.
one of a series of rudimentary depressions on the surface of the embryo between adjacent branchial arches, homologous to the branchial clefts of gill-breathing ancestral forms.