/ Dictionary / Index R rat snake: Meaning and Definition of Find definitions for: rat' snake" Pronunciation: [key] any of several New and Old World colubrid snakes, of the genus Elaphe, that feed chiefly on small mammals and birds. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ratsbane rat's nest Related Content Daily Word Quiz: lyceum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language