vi·​per | \ ˈvī-pər How to pronounce viper (audio) \

Definition of viper

1a : a common Eurasian venomous snake (Vipera berus) that attains a length of about two feet (0.6 meter), varies in color from red, brown, or gray with dark markings to black, and is usually not fatal to humans broadly : any of a family (Viperidae) of venomous snakes that includes Old World snakes (subfamily Viperinae) and the pit vipers
b : a venomous or reputedly venomous snake
2 : a vicious or treacherous person

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Synonyms for viper


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Examples of viper in a Sentence

a viper sliding silently through the field
Recent Examples on the Web Hudson, who manned the Wolverines' viper position, was projected as a mid- to late-round pick entering the draft. Orion Sang, Detroit Free Press, "Washington takes Michigan LB Khaleke Hudson in Round 5 of 2020 NFL draft," 25 Apr. 2020 Because the actual rhino viper moms and dads basically leave their offspring to fend for themselves. Meg Jones, Milwaukee Journal Sentinel, "Baby rhinoceros vipers slither their way into the hearts of Milwaukee County zookeepers," 2 Oct. 2019 Taken together, these similarities suggest the toad is a near-perfect mimic for the viper, the researchers write today in the Journal of Natural History. Munyaradzi Makoni, Science | AAAS, "One of these is a deadly viper. The other is a harmless toad. Can you tell the difference?," 20 Oct. 2019 Charlie's Angels pounces out of the long grass with a viper's speed and a tiger's strength. Isaac Feldberg, Fortune, "What to Watch (and Skip) in Theaters and on Netflix This Weekend," 15 Nov. 2019 Among them are Blackett’s feckless, dissolute son, Monty, who is scheming to avoid military service; his daughter, Joan, a human viper; and the Human Condition, an elderly, mangy spaniel with his own preoccupations. Katherine A. Powers, Washington Post, "The sordid tale of the Borgias and other great audiobooks for your playlist," 26 Sep. 2019 Co-defensive coordinator Greg Mattison brought the bullet — which will be manned by Brendon White on Saturday — with him from Michigan where it is called the viper. Stephen Means,, "Ohio State will get a good evaluation of the bullet position against Florida Atlantic: Game-Time Decision," 31 Aug. 2019 Asghari spent his youth catching vipers in the mountains by his home in Tehran. Jack Brook,, "Iranian, Canadian among 2,600 to apply for 50 Florida Everglades python hunter jobs," 31 Oct. 2019 Nicole gets an acting gig on a TV show in L.A. and, after being nudged to make the best deal for herself and Henry, her and Charlie’s eight-year-old son, settles into the couch of an expensively clad viper played by Laura Dern. Kyle Smith, National Review, "Divorce, Brooklyn Style," 8 Oct. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'viper.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of viper

15th century, in the meaning defined at sense 1a

History and Etymology for viper

Middle English vipere, from Latin vipera

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Time Traveler for viper

Time Traveler

The first known use of viper was in the 15th century

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Statistics for viper

Last Updated

8 May 2020

Cite this Entry

“Viper.” Dictionary, Merriam-Webster, Accessed 29 May. 2020.

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How to pronounce viper (audio)

English Language Learners Definition of viper

: a type of poisonous snake


vi·​per | \ ˈvī-pər How to pronounce viper (audio) \

Kids Definition of viper

: a poisonous heavy-bodied snake with long hollow fangs


vi·​per | \ ˈvī-pər How to pronounce viper (audio) \

Medical Definition of viper

1 : a common Eurasian venomous snake of the genus Vipera (V. berus) that attains a length of about two feet (0.6 meter), varies in color from red, brown, or gray with dark markings to black, and whose bite is usually not fatal to humans broadly : any snake of an Old World subfamily (Viperinae) of the family Viperidae
3 : a venomous or reputedly venomous snake

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More from Merriam-Webster on viper

Thesaurus: All synonyms and antonyms for viper

Rhyming Dictionary: Words that rhyme with viper

Spanish Central: Translation of viper

Nglish: Translation of viper for Spanish Speakers

Britannica English: Translation of viper for Arabic Speakers Encyclopedia article about viper

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