/ Dictionary / Index G graph theory: Meaning and Definition of Find definitions for: graph' the"ory Pronunciation: [key] — Math. Math. the branch of mathematics dealing with linear graphs. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. graph paper -graphy 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