/ Dictionary / Index S supply-sider: Meaning and Definition of Find definitions for: sup•ply-sid•er Pronunciation: (su-plī'sī"dur), [key] — n. a person, esp. an economist, who advocates supply-side economics. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. supply-side support Related Content Daily Word Quiz: endear Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language