• (n. pl.) A division of ganoid fishes including those that have large external bony plates and a cartilaginous skeleton.
Plac`o·ga·noi'de·i noun plural [ New Latin , from Greek ..., ..., a tablet + New Latin ganoidei . See Ganoidei .] (Zoology) A division of ganoid fishes including those that have large external bony plates and a cartilaginous skeleton.