adder

1 of 2

noun (1)

ad·​der ˈa-dər How to pronounce adder (audio)
1
: the common venomous viper (Vipera berus) of Europe
broadly : any of various snakes of the viper family compare puff adder
2
: any of several North American snakes (such as the hognose snakes) that are harmless but are popularly believed to be venomous

Illustration of adder

Illustration of adder
  • adder 1

adder

2 of 2

noun (2)

add·​er ˈa-dər How to pronounce adder (audio)
: one that adds
especially : a device (as in a computer) that performs addition

Did you know?

How Adder Lost Its First Letter

Words formed by what linguists call “false division,” “misdivision,” or “metanalysis” have spellings that record a mistake that was made at some point in their history, when the spelling or sound of the word was split in the wrong place.

Misdivisions of words that begin with the letter n are frequent because, in speech, it is difficult to distinguish between the sound of the indefinite article “a” followed by a word beginning with an n (as in “a name”) and the sound of the indefinite article “an” followed by a word beginning with a vowel (as in “an aim”). This make the position of the n very easily confused.

An example is the name of the venomous snake known as the adder. The Old English word for this viper was nǣdre, which became nadder in Middle English. Over time, a nadder became an adder. By by the mid-1400s, the word was being spelled both with and without the n, but since about 1500, the n-less spelling has prevailed.

Examples of adder in a Sentence

Recent Examples on the Web
Noun
Known by a host of common names—trout lily, fawn lily, and adder's tongue—this woodland wildflower is a harbinger of spring. Nadia Hassani, Better Homes & Gardens, 31 Jan. 2024 The Australian death adder spends most of its days hidden in leaf litter, often with only the tip of its tail exposed. Elizabeth Kolbert, The New Yorker, 27 Mar. 2023 Biologists found that death adders possess clitorises, then went on to locate them in eight other species of snakes. Matthew Gavin Frank, Harper's Magazine, 21 Mar. 2023 Australian scientists who played sounds for snakes found that woma pythons tend to move toward pink noise while death adders tend to move away. Michael W. Clune, Harper’s Magazine , 10 Apr. 2023 Another team built a three-input, two-output full adder (a circuit that literally adds up numbers), which combines different types of logic gates, in human embryonic cells. Eric Smalley, Discover Magazine, 2 Jan. 2019 When an unsuspecting lizard takes the bait, the death adder strikes. Elizabeth Kolbert, The New Yorker, 27 Mar. 2023 The researchers were able to build functional circuitry across the entirety of a 2-inch wafer, including half-adder units, an essential component of computational hardware. John Timmer, Ars Technica, 21 Mar. 2023 And the child lay his hand on the adder’s lair. George Stanley, Journal Sentinel, 6 Jan. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'adder.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun (1)

Middle English addre, eddre, alteration (resulting from misdivision of a naddre) of naddre, neddre, going back to Old English nǣdre "adder, snake," going back to West Germanic nēdrōn- (whence also Old Saxon nādra "grass snake [Natrix natrix or allied species]," Old High German nātara, nāter), going back to dialectal (western) Indo-European *neh1tr-, full-grade ablaut of *nh1tr- (whence Old Norse naðr "adder, snake," Gothic nadrs "snake, viper," Latin natric-, natrix "water snake [as Natrix maura]," Old Irish nathir [genitive singular nathrach] "snake," Welsh neidr [plural nadredd], Breton aer, naer "grass snake"), perhaps from *(s)neh1- "twist together, spin" + *-tr-, -ter-, agent suffix (hence "one who winds, twists") — more at needle entry 1

Noun (2)

add + -er entry 2

First Known Use

Noun (1)

14th century, in the meaning defined at sense 1

Noun (2)

1547, in the meaning defined above

Time Traveler
The first known use of adder was in the 14th century

Dictionary Entries Near adder

Cite this Entry

“Adder.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/adder. Accessed 24 Feb. 2024.

Kids Definition

adder

1 of 2 noun
ad·​der ˈad-ər How to pronounce adder (audio)
1
: a poisonous European viper
also : any of several related snakes
2
: any of several harmless North American snakes (as the hognose snakes)

adder

2 of 2 noun
add·​er ˈad-ər How to pronounce adder (audio)
: one that adds

Medical Definition

adder

noun
ad·​der ˈad-ər How to pronounce adder (audio)
1
: the common venomous European viper of the genus Vipera (V. berus)
broadly : a terrestrial viper of the family Viperidae
2
: any of several North American snakes (as the hognose snakes) that are harmless but are popularly believed to be venomous
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