/ Dictionary / Index A aperiodic: Meaning and Definition of Find definitions for: a•pe•ri•od•ic Pronunciation: (ā"pēr-ē-od'ik), [key] — adj. not periodic; irregular. of or pertaining to vibrations or oscillations with no apparent period. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: aperiodic (Thesaurus) aperient apéritif Related Content Daily Word Quiz: blithesome Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language