pit viper

American  

noun

1. any of numerous venomous snakes of the family Crotalidae, of the New World, Asia, and the Malay Archipelago, as the rattlesnake, water moccasin, and copperhead, having a heat-sensitive pit on each side of the head between the eye and nostril.

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pit viper British  

noun

1. any venomous snake of the New World family Crotalidae, having a heat-sensitive organ in a pit on each side of the head: includes the rattlesnakes

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pit viper Scientific  

1. Any of various very venomous snakes of the family Crotalidae. Pit vipers are characterized by a triangular head with a small sensory pit below each eye. The pits detect infrared radiation and help the snake locate prey. Some scientists classify the pit vipers as a subfamily Crotalinae within the Viperidae, the family of vipers, rather than as a separate family. Copperheads, rattlesnakes, and fer-de-lances are pit vipers.

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Etymology

Origin of pit viper

First recorded in 1880–85

Example Sentences

See Examples For:

pit viper

Some populations are dark green with obvious blotches, making them fairly easy to distinguish from the redtail pit viper, which is bright green and unmarked.

From Science Daily ● Apr. 21, 2026

These include the green pit viper commonly found in the northern state of Himachal Pradesh, the Malabar pit viper and hump-nosed pit viper found in southern states and many other species in the north-eastern states.

From BBC ● Feb. 1, 2026

For instance, pit viper venom has already led to the development of a blood pressure medication.

From National Geographic ● Feb. 13, 2024

These rivers and their associated basins also mark the westernmost and easternmost distribution boundaries of the Ayeyarwady pit viper.

From Science Daily ● Dec. 21, 2023

Ned would sooner entrust a child to a pit viper than to Lord Tywin, but he left his doubts unspoken.

From "A Game of Thrones" by George R.R. Martin