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Synonyms

adder

1 American  
[ad-er] / ˈæd ər /

noun

  1. the common European viper, Vipera berus.

  2. any of various other venomous or harmless snakes resembling the viper.


adder 2 American  
[ad-er] / ˈæd ər /

noun

  1. a person or thing that adds.


adder 1 British  
/ ˈædə /

noun

  1. Also called: viper.  a common viper, Vipera berus, that is widely distributed in Europe, including Britain, and Asia and is typically dark greyish in colour with a black zigzag pattern along the back

  2. any of various similar venomous or nonvenomous snakes

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adder 2 British  
/ ˈædə /

noun

  1. a person or thing that adds, esp a single element of an electronic computer, the function of which is to add a single digit of each of two inputs

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of adder1

before 950; late Middle English; replacing Middle English nadder ( a nadder becoming an adder by misdivision; apron ), Old English næddre; cognate with Old Saxon nādra, Old High German nātara ( German Natter ), Old Norse nathra snake, Gothic nadrs adder, Old Irish nathir snake, Latin natrix water snake

Origin of adder2

First recorded in 1570–80; add + -er 1

Vocabulary lists containing adder

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But if something goes wrong using the so-called adder strategy, the cell takes longer to get back to its original size.

From Science Daily • Apr. 17, 2024

They can strike with the venom of an adder when the moment arrives.

From BBC • Apr. 29, 2023

To investigate, Ms. Folwell set about dissecting the tail of a female death adder.

From New York Times • Dec. 13, 2022

A debut novel as slender and deadly as an adder, “Assembly” follows a young Black British woman preparing to attend a party at her boyfriend’s family estate.

From Los Angeles Times • Aug. 24, 2021

“Well, let’s get started, friend Log-a-Log. We’ve got an adder to fight and a sword to win!”

From "Redwall" by Brian Jacques