/ak'teuh nop'teuh rij"ee euhn/ , adj.
1. belonging or pertaining to the Actinopterygii, a group of bony fishes.
n.
2. an actinopterygian fish.
[ Actinopterygi ( i ) (pl.) ( actino- ACTINO- + Gk pterýgi ( on ) fin, equiv. to pteryg- (s. of ptéryx wing) + -ion dim. suffix) + -AN ]