PLACODERM
Plac"o*derm, n. Etym: [Gr. (Paleon.)
Defn: One of the Placodermi.
PLACODERMAL
Plac`o*der"mal, a. (Paleon.)
Defn: Of or pertaining to the placoderms; like the placoderms.
PLACODERMATA
Plac`o*der"ma*ta, n. pl. Etym: [NL.] (Paleon.)
Defn: Same as Placodermi.
PLACODERMI
Plac`o*der"mi, n. pl. Etym: [NL., fr. Gr. (Paleon.)
Defn: An extinct group of fishes, supposed to be ganoids. The body and head were covered with large bony plates. See Illust. under Pterichthys, and Coccosteus.
PLACOGANOID
Plac`o*ga"noid, a. (Zoöl.)
Defn: Pertaining to the Placoganoidei.