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Added 7 October 2026

acid

/ˈæsɪd/ adjective

In Latin: acidus Wiktionary

adjective Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about acid at Wordnik → Where our words come from →

Sour, sharp, or biting to the taste; tart; having the taste of vinegar.
acid fruits or liquors
Sour-tempered.
His response was harsh and acid.
Of or pertaining to an acid; acidic.
acid soils

noun

A sour substance.
Any compound which yields H+ ions (protons) when dissolved in water; an Arrhenius acid.
Any compound that easily donates protons to a base; a Brønsted acid.

Origin

From French acide, from Latin acidus (“sour, acid”), from aceō (“to be sour”). Doublet of agita.

From Wiktionary, via Kaikki.org (CC BY-SA)

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