/ Dictionary / Index P photonuclear: Meaning and Definition of Find definitions for: pho•to•nu•cle•ar Pronunciation: (fō"tō-n'klē-ur, -ny'- or, by metathesis, -kyu-lur), [key] — adj. Physics. of, pertaining to, or caused by the collision of high-energy photons with the nucleus of an atom. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. photonovel photo-offset Related Content Daily Word Quiz: resilient Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language