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 vipersb : a venomous or reputedly venomous snake
2 : a vicious or treacherous person
Examples of viper in a Sentence
a viper sliding silently through the field
Recent Examples of viper from the Web
Waters said his Viper demo team is scheduled on the air show circuit through November with few days off.
Character: ViperSince 1986: Listen, Tom Skerritt has had a very long and illustrious career.
After being bitten by pit vipers, some Brazilian plantation workers were observed to collapse and suffer plummeting blood pressure.
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.
Origin and Etymology of viper
Middle English vipere, from Latin vipera
First Known Use: 15th centurySee Words from the same year
VIPER Defined for English Language Learners
Definition of viper for English Language Learners
: a type of poisonous snake
VIPER Defined for Kids
Definition of viper for Students
: a poisonous heavy-bodied snake with long hollow fangs
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
2: pit viper
3: a venomous or reputedly venomous snake
Seen and Heard
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