n. (Zool.) Any one of several species of venomous American snakes belonging to the genera Crotalus and Caudisona, or Sistrurus; sometimes also called rattler. They have a series of horny interlocking joints at the end of the tail which make a sharp rattling sound when shaken. The common rattlesnake of the Northern United States (Crotalus horridus), and the diamondback rattlesnake (also called diamondback rattler, and diamondback) of the South and East (Crotalus adamanteus) and West (Crotalus atrox), are the best known. See Illust. of Fang. [ 1913 Webster +PJC ]

Ground rattlesnake (Zool.), a small rattlesnake (Caudisona miliaria or Sistrurus miliaria) of the Southern United States, having a small rattle. It has nine large scales on its head. --
Rattlesnake fern (Bot.), a common American fern (Botrychium Virginianum) having a triangular decompound frond and a long-stalked panicle of spore cases rising from the middle of the frond. --
Rattlesnake grass (Bot.), a handsome American grass (Glyceria Canadensis) with an ample panicle of rather large ovate spikelets, each one composed of imbricated parts and slightly resembling the rattle of the rattlesnake. Sometimes called quaking grass. --
Rattlesnake plantain (Bot.), See under Plantain. --
Rattlesnake root (Bot.), a name given to certain American species of the composite genus Prenanthes (Prenanthes alba and Prenanthes serpentaria), formerly asserted to cure the bite of the rattlesnake. Called also lion's foot, gall of the earth, and white lettuce. --
Rattlesnake's master (Bot.) (a) A species of Agave (Agave Virginica) growing in the Southern United States. (b) An umbelliferous plant (Eryngium yuccaefolium) with large bristly-fringed linear leaves. (c) A composite plant, the blazing star (Liatris squarrosa). --
Rattlesnake weed (Bot.), a plant of the composite genus Hieracium (Hieracium venosum); -- probably so named from its spotted leaves. See also Snakeroot. [ 1913 Webster ]