/ Dictionary / Index A aperiodic: Meaning and Definition of Find definitions for: a•pe•ri•od•ic Pronunciation: (?"p?r-?-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 apritif Related Content Daily Word Quiz: ravenous Analogy of the Day: Today?s Analogy Spelling Bee: Today?s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language