/ Dictionary / Index E eigenfunction: Meaning and Definition of Find definitions for: ei•gen•func•tion Pronunciation: (ī'gun-fungk"shun), [key] — n. Math. a characteristic vector in a vector space in which the elements are functions. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Eigen eigenvalue Related Content Daily Word Quiz: supercilious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language