American pit vipers are venomous snakes that belong to the Crotalinae subfamily. They are native to North, Central, and South America. These pit vipers are known for their triangular-shaped heads, venomous fangs, and heat-sensing pits situated between their eyes and nostrils. The term "american pit viper" is the most commonly used, but there are other synonyms that you should be aware of. Some of the other names used for this species include the eastern diamondback rattlesnake, timber rattlesnake, Pacific rattlesnake, copperhead snake, and cottonmouth snake. These synonyms help in the identification and classification of these snakes in different regions.