ˈ ̷ ̷ ̷ ̷ˌ ̷ ̷ noun
: any of numerous New World pit vipers that have a series of horny interlocking joints at the end of the tail which make a sharp rattling sound when vibrated, that comprise two genera of which one ( Sistrurus ) contains small snakes (as the massasaugas and ground rattlesnakes) having the head covered with symmetrical plates and the other ( Crotalus ) contains usually larger snakes that have scales instead of headplates, are rather thick-bodied, large-headed snakes of sluggish disposition which seldom bite unless startled or pursuing prey, and occur across most of America from southern Canada to Argentina — see canebrake rattler , diamondback rattlesnake , prairie rattlesnake , sidewinder , timber rattlesnake , western diamond rattlesnake
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