/ Dictionary / Index A actinopterygian: Meaning and Definition of Find definitions for: ac•ti•nop•te•ryg•i•an Pronunciation: (ak"tu-nop"tu-rij'ē-un), [key] — adj. belonging or pertaining to the Actinopterygii, a group of bony fishes. —n. an actinopterygian fish. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. actinopod actinotherapy Related Content Daily Word Quiz: menagerie Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language