The term 'Diamondback' refers to three different species of animals. The first is the TERRAPIN, which is a type of turtle found in the eastern United States and Canada. The second is the Rattler, which is a type of snake found in the southwestern United States and Mexico. The third is the RATTLESNAKE, which is a type of venomous snake found throughout North America. All three species have diamond-shaped patterns on their backs, hence the name 'Diamondback'.