especially: a device (as in a computer) that performs addition
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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.
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