/ Dictionary / Index P periodicity: Meaning and Definition of Find definitions for: pe•ri•o•dic•i•ty Pronunciation: (pēr"ē-u-dis'i-tē), [key] — n. the character of being periodic; the tendency to recur at regular intervals. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: periodicity (Thesaurus) periodic function periodic law Related Content Daily Word Quiz: diligent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language