Definition

Noun: 1. A common name for two distinct types of snakes: * A harmless colubrid snake (Heterodon platirhinos) native to North America, also commonly called the "hognose snake." It is known for its upturned snout and defensive behavior of flattening its head and neck or feigning death when threatened. * A highly venomous viper (Cerastes vipera) found in the deserts of North Africa and the southwestern Middle East. It is characterized by the presence of a small, horn-like scale above each eye and is known for its sidewinding locomotion.

Usage Examples

• Referring to the harmless North American snake:
  • The children found a sand viper in the field, but it was just a harmless hognose snake playing dead.
  • Unlike true vipers, the North American sand viper is not venomous to humans.
• Referring to the venomous African/Asian viper:
  • Extreme caution is advised in the Sahara due to the presence of the sand viper, whose bite can be fatal.
  • The sand viper uses its sidewinding motion to move efficiently across loose desert sand.

Advanced Usage & Notes

• The term "sand viper" is an example of a common name that can refer to completely different species in different parts of the world. This can cause confusion. In scientific or precise contexts, the Latin binomial names ( and ) are used to avoid ambiguity.
• The defensive behavior of the North American species (playing dead, head-flattening) is a bluff to intimidate predators, as it lacks potent venom.

Variants and Related Words

• Hognose snake: The more precise and common name for the harmless North American species.
• Horned viper: A common name often used interchangeably for the venomous species, particularly which has more prominent "horns."
• Puff adder: Another common name sometimes used for the African species, which is different from the sand viper. This highlights the importance of scientific names.

Synonyms

• For the harmless snake: Eastern hognose snake, hissing adder (colloquial, misleading).
• For the venomous snake: Sahara sand viper, Avicenna viper.

Related Idioms/Phrases

• To play possum / to play dead: This idiom, meaning to pretend to be dead or unconscious, perfectly describes the primary defensive tactic of the North American sand viper (hognose snake).
  • When the dog approached, the sand viper decided to play dead until the threat passed.

Noun

1. harmless North American snake with upturned nose; may spread its head and neck or play dead when disturbed
2. highly venomous viper of northern Africa and southwestern Asia having a horny spine above each eye