viper

—viperish, adj. —viperishly, adv.

/vuy"peuhr/, n.

1. any of several venomous Old World snakes of the genus Vipera, esp. V. berus, a small snake common in northern Eurasia.

2. any related snakes belonging to the family Viperidae, characterized by erectile, venom-conducting fangs.

3. See pit viper.

4. any of various venomous or supposedly venomous snakes.

5. a malignant or spiteful person.

6. a false or treacherous person.

7. (cap.) Mil. a 9-pound (4 kg), shoulder-launched, unguided U.S. Army antitank rocket with an effective range of 273 yds. (250 m).

8. to nourish a viper in one's bosom, to befriend a person who proves to be treacherous.

[1520-30; < L vipera, haplological var. of *vivipera, n. use of fem. of *viviper, later (as re-formation) viviparus VIVIPAROUS]

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Any of about 200 species (family Viperidae) of venomous snakes in two subfamilies: Viperinae (Old World vipers of Europe, Asia, and Africa) and Crotalinae (pit vipers).

Two long, hollow, venom-injecting fangs attached to the movable bones of the viper's upper jaw can be folded back in the mouth when not in use. Vipers range in length from less than 12 in. (30 cm) to more than 10 ft (3 m). They eat small animals and hunt by striking, then trailing, their prey. Many Old World vipers are terrestrial; a few are arboreal or burrowers. Most bear live young.

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▪ snake

      any of more than 200 species of venomous snakes belonging to two groups: pit vipers (subfamily Crotalinae) and Old World vipers (subfamily Viperinae), which are considered separate families by some authorities. They eat small animals and hunt by striking and envenomating their prey. Vipers are characterized by a pair of long, hollow, venom-injecting fangs attached to movable bones of the upper jaw (the maxillaries) that are folded back in the mouth when not in use. Their eyes have vertical pupils, and their scales are keeled. Vipers range in length from less than 25 cm (10 inches) in the Namaqua dwarf viper (Bitis schneideri) of southern Africa to more than 3 metres (10 feet) in the bushmaster (Lachesis muta) of the Amazon (Amazon River) basin and Central America.

 The pit vipers are found from desert to rainforest, primarily in the New World. This group includes copperheads, rattlesnakes, and fer-de-lances (genus Bothrops), among others. They may be terrestrial or arboreal. Some, such as the moccasins (genus Agkistrodon), are aquatic. Except for the egg-laying bushmaster, all pit vipers are live-bearers (viviparous).

      Pit vipers are distinguished by a temperature-sensitive pit organ located on each side of the head midway between each nostril and eye. This structure is sensitive to infrared radiation, which enables the snake to “see” heat images of warm-blooded prey. As a pair, they provide a form of binocular vision that helps the snake accurately aim its strike at warm-blooded prey. At least some Old World vipers have infrared receptors in the same area as the pit organs, although there is no external evidence of them. Some boas and pythons have similar infrared organs located in pits between the lip scales.

 Old World vipers live in desert to forest habitats of Europe, Asia, and Africa. They are typically slow, stocky, and broad-headed. Many, such as the European viper, or common adder (Vipera berus), and the Gaboon viper (Bitis gabonica) are terrestrial, but tree vipers (genus Atheris) are slender, prehensile-tailed, and arboreal. Some species lay eggs; others produce live young.

 

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