The posterior regarding the two bones which edge the top of jaw in osseous fishes. It usually bears teeth when you look at the soft-rayed fishes, however in the spiny-rayed fishes tooth tend to be confined into the prem axillary.
the jaw in vertebrates that's fused toward cranium
Of or pertaining by any means to a jaw or jaw-bone; specifically, of or related to the maxilla alone, in every of special senses of that term: as, the maxillary bones of a vertebrate; the maxillary palps of an insect.
How would you define maxillary?