acid

noun
\ ˈa-səd How to pronounce acid (audio) \

Definition of acid

 (Entry 1 of 2)

1 : a sour substance specifically : any of various typically water-soluble and sour compounds that in solution are capable of reacting with a base (see base entry 1 sense 6a) 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 : something incisive, biting, or sarcastic a social satire dripping with acid
3 : lsd

acid

adjective

Definition of acid (Entry 2 of 2)

1a : 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
2a : 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 : relating to or made by a process in which the furnace is lined with acidic material and an acidic slag is used acid steel
4 : rich in silica acid rocks

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Other Words from acid

Noun

acidy \ ˈa-​sə-​dē \ adjective

Adjective

acidly adverb
acidness noun

Synonyms for acid

Synonyms: Adjective

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Examples of acid in a Sentence

Noun the acids in your stomach the kinds of acid found in your stomach Adjective He washes his windows with an acid solution of vinegar and water. with her acid personality, my aunt could be relied upon to bring some much-needed balance to the holiday gush
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Recent Examples on the Web: Noun Like a Disney movie on acid, teapots and cutlery begin to murmur, scream and dictate to him; a beloved antique spoon laments its many losses. Mary Ann Gwinn, Los Angeles Times, 23 Sep. 2021 The serum also contains 1.1% tranexamic acid, which has been studied extensively over the past several years in oral formulations in the treatment of hyperpigmentation, including melasma. Sarah Jacob, SELF, 6 Sep. 2021 Tangerine and clementine orange notes, small red fruits, tart and fresh with good mouthwatering acid, slightly tropical: guava and pineapple. Lana Bortolot, Forbes, 28 Aug. 2021 The leak of acetic acid, a food preservative commonly used in vinegar, which can be flammable, happened at 7:35 p.m. Tuesday at the LyondellBasell facility, which is the world’s third largest producer of the acid, according to the company. Washington Post, 28 July 2021 The media coverage focused on the white-glove treatment, the acid-free paper used to wrap the artifacts, and so on. BostonGlobe.com, 13 Sep. 2021 The pop star and beauty mogul was photographed at a Whole Foods in New York City wearing a tweed blazer with shoulder pads and gold hardware, a lacy black bra, and loose acid-washed jeans. Quinci Legardye, Harper's BAZAAR, 17 Aug. 2021 On the west side of the Cascades, pH greater than 7.0 is uncommon, so gardeners typically only acidify their soil for growing acid-loving plants like rhododendrons and blueberries. oregonlive, 26 July 2021 Acid-producing and acid-loving bacteria are the primary culprits in dissolving the enamel, which protects the tooth. Jeffrey Ebersole, The Conversation, 18 May 2021 Recent Examples on the Web: Adjective To the left of the door sits a rack full of acid wash jeans, floral frocks, paper-thin nightdresses, and antique quilts, piled high to the ceiling. Kristen Bateman, Vogue, 12 Oct. 2021 The victim had acid thrown over her face, neck and chest. Harriet Sokmensuer, PEOPLE.com, 11 Oct. 2021 That same year, ballet soloist Pavel Dmitrichenko was ordered jailed for six years by a Moscow court for his role in a brutal acid attack on the company’s artistic director, Sergei Filin, that left him almost blind. Washington Post, 10 Oct. 2021 Omeprazole and other proton pump inhibitors effectively stop acid production in the stomach. Dr. Keith Roach, oregonlive, 30 Sep. 2021 Environmentalists have fought it because of the potential for acid mine drainage. From Usa Today Network And Wire Reports, USA TODAY, 27 Sep. 2021 Expect superb, intense red wine made from the local Vranac grape, its acid freshness is derived from the chillier temperatures that vineyards often weather here versus across the water in Italy. Mark Ellwood, Robb Report, 22 Sep. 2021 The American rapper’s acid green dye job and sooty eye makeup nodded at Dennis Rodman’s ’90s party days, or the pop punk revival seen in a recent return of the noughties genre’s figureheads like Travis Barker and Avril Lavigne. Arden Fanning Andrew, Vogue, 13 Sep. 2021 Now 80, he has been diagnosed over the years with acid reflux disease, asthma, and also thyroid cancer and skin melanoma, for which he was successfully treated. David B. Caruso, Anchorage Daily News, 10 Sep. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'acid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of acid

Noun

1650, in the meaning defined at sense 1

Adjective

1649, in the meaning defined at sense 1a

History and Etymology for acid

Noun

borrowed from Medieval Latin acidum, going back to Latin, neuter of acidus acid entry 2

Adjective

borrowed from French & Latin; French acide, going back to Middle French, borrowed from Latin acidus, adjective derivative from the base of acēre "to be sour" — more at acetic acid

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Learn More About acid

Dictionary Entries Near acid

aciculum

acid

acid alizarin red B

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Statistics for acid

Last Updated

15 Oct 2021

Cite this Entry

“Acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acid. Accessed 17 Oct. 2021.

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More Definitions for acid

acid

noun

English Language Learners Definition of acid

 (Entry 1 of 2)

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

acid

adjective

English Language Learners Definition of acid (Entry 2 of 2)

: of, relating to, or having the qualities of an acid
: sharp, strong, and critical in tone

acid

adjective
ac·​id | \ ˈa-səd How to pronounce acid (audio) \

Kids Definition of acid

 (Entry 1 of 2)

1 : having a taste that is sour, bitter, or stinging
2 : harsh or critical in tone acid remarks
3 : of, relating to, or like an acid an acid solution

Other Words from acid

acidly adverb spoke acidly

acid

noun

Kids Definition of acid (Entry 2 of 2)

: a chemical compound that tastes sour and forms a water solution which turns blue litmus paper red

acid

adjective
ac·​id | \ ˈas-əd How to pronounce acid (audio) \

Medical Definition of acid

 (Entry 1 of 2)

1 : sour, sharp, or biting to the taste
2a : of, relating to, or being an acid also : having the reactions or characteristics of an acid an acid solution
b of salts and esters : derived by partial exchange of replaceable hydrogen acid sodium carbonate NaHCO3
c : marked by or resulting from an abnormally high concentration of acid acid indigestion not used technically

acid

noun

Medical Definition of acid (Entry 2 of 2)

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, that redden litmus, that have a pH less than 7, and that are hydrogen-containing molecules or ions able to give up a proton to a base or are substances able to accept an unshared pair of electrons from a base
2 : lsd

More from Merriam-Webster on acid

Nglish: Translation of acid for Spanish Speakers

Britannica English: Translation of acid for Arabic Speakers

Britannica.com: Encyclopedia article about acid

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