/ Dictionary / Index S supplementary: Meaning and Definition of Find definitions for: sup•ple•men•ta•ry Pronunciation: (sup"lu-men'tu-rē), [key] — adj., n., pl. -ries. —adj. of the nature of or forming a supplement; additional. —n. a person or thing that is supplementary. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: supplementary (Thesaurus) Supplemental Security Income supplementary angle Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language