Definition of "moonfish"

Any of various flat, oval marine fish species.

1. Family Monodactylidae (fingerfishes, silver angelfishes)  examples

2. Mene maculata, of tropical coastal waters of the Indo-Pacific  examples

3. Most species of genus Selene  examples

4. Atlantic spadefish (Chaetodipterus faber)  examples

5. Family Molidae (ocean sunfish)  examples

6. The opahs in the family Lamprididae.  examples

7. The cusk (Brosme brosme), a North Atlantic cod-like fish in the ling family Lotidae, the only species in its genus.  examples

8. The southern platyfish (Xiphophorus maculatus)  examples