/ Dictionary / Index R rattlesnake: Meaning and Definition of Find definitions for: rat•tle•snake Pronunciation: (rat'l-snāk"), [key] — n. any of several New World pit vipers of the genera Crotalus and Sistrurus, having a rattle composed of a series of horny, interlocking elements at the end of the tail. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rattlesnake (Thesaurus) rattler rattlesnake fern Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language