/ Dictionary / Index P pereion: Meaning and Definition of Find definitions for: pe•rei•on Pronunciation: (pu-rī'on, -rā'-, -rē'-), [key] — pl. -rei•a (in a crustacean) the thorax. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. peregrine falcon pereiopod Related Content Daily Word Quiz: dissonant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language