gan·oid 
(gănoid′)
(gănoid′)adj.
1. Relating to or being a kind of fish scale that is hard and bony with a shiny surface composed of an enamel-like substance.
2. Having ganoid scales.
n.
A fish having ganoid scales, such as a gar or sturgeon.
[From New Latin Ganoideī, former subclass name, from Greek ganos, brightness, gladness (in reference to the shiny scales of the fish included in the subclass), from ganusthai, to rejoice; see gāu- in the Appendix of Indo-European roots.]