/ Dictionary / Index N nonperformance: Meaning and Definition of Find definitions for: non•per•form•ance Pronunciation: (non"pur-fôr'muns), [key] — n. failure or neglect to perform. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: nonperformance (Thesaurus) nonpeak nonperformer Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language