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adjective ac·id \ˈa-səd\

Simple Definition of acid

  • : of, relating to, or having the qualities of an acid

  • : sharp, strong, and critical in tone

Full Definition of acid

  1. 1 a :  sour, sharp, or biting to the taste <an acid flavor> b :  sharp, biting, or sour in manner, disposition, or nature <an acid individual> <an acid personality> c :  sharply clear, discerning, or pointed <an acid wit> <acid criticism> d :  piercingly intense and often jarring <acid yellow>

  2. 2 a :  of, relating to, or being an acid; also :  having the reactions or characteristics of an acid <acid soil> <an acid solution> b of salts and esters :  derived by partial exchange of replaceable hydrogen <acid sodium carbonate NaHCO3> c :  containing or involving the use of an acid (as in manufacture) <an acid bath> d :  marked by or resulting from an abnormally high concentration of acid <acid indigestion>

  3. 3 :  relating to or made by a process (as in making steel) in which the furnace is lined with acidic material and an acidic slag is used

  4. 4 :  rich in silica <acid rocks>

ac·id·ly adverb
ac·id·ness noun

Examples of acid

  1. He washes his windows with an acid solution of vinegar and water.

  2. <with her acid personality, my aunt could be relied upon to bring some much-needed balance to the holiday gush>

Origin of acid

French or Latin; French acide, from Latin acidus, from acēre to be sour — more at acet-

First Known Use: 1626

Other Chemical Engineering Terms

Rhymes with acid



noun ac·id

Simple Definition of acid

  • chemistry : a chemical with a sour taste that forms a salt when mixed with a base

Full Definition of acid

  1. 1 :  a sour substance; specifically :  any of various typically water-soluble and sour compounds that in solution are capable of reacting with a base to form a salt, redden litmus, and have a pH less than 7, that are hydrogen-containing molecules or ions able to give up a proton to a base, or that are substances able to accept an unshared pair of electrons from a base

  2. 2 :  something incisive, biting, or sarcastic <a social satire dripping with acid>

  3. 3 :  lsd

ac·idyplay \ˈa-sə-dē\ adjective

Examples of acid

  1. the acids in your stomach

  2. the kinds of acid found in your stomach


First Known Use of acid


Other Chemical Engineering Terms

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February 11, 2016

the holder of an office

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