dinichthys

from The Century Dictionary.

• noun A genus of gigantic arthrodirous Devonian fishes, regarded as pertaining to the family Coccosteidæ, in which the head-shield is comprised of one large median occipital plate, and three pairs of lateral and two pairs of anterior plates, the trunk also being plated.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Paleon.) A genus of large extinct Devonian ganoid fishes. In some parts of Ohio remains of the Dinichthys are abundant, indicating animals twenty feet in length.