/ Dictionary / Index P postatomic: Meaning and Definition of Find definitions for: post•a•tom•ic Pronunciation: (pōst"u-tom'ik), [key] — adj. existing since or subsequent to the explosion of the first atomic bomb or the invention of atomic weapons: the political tensions of the postatomic world. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. post-and-beam construction postaudit Related Content Daily Word Quiz: kiln Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language