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

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
Recent Examples on the Web: Noun Muriatic acid: This substance is commonly used on driveways or garage floors where oil leaks from a car have stained the concrete. Nafeesah Allen, Better Homes & Gardens, 23 June 2022 Designer Khaled El Mays’ collection at Nilufar Depot felt like an enchanting jungle room on acid. Damon Johnstun, oregonlive, 26 May 2022 The crux of an agrodolce is a warmed sweetener like sugar or honey paired with a hit of acid, usually in the form of vinegar. Christian Reynoso, Bon Appétit, 26 May 2022 From there, the director pours on the acid — and the diarrhea, and the vomit — in some of the most remarkably modulated and attenuated gross-out comedy scenes in recent memory. Justin Changfilm Critic, Los Angeles Times, 22 May 2022 When rice is cooked, it can be seasoned with more spices or a touch of acid, like lemon. Nicole Papantoniou, Good Housekeeping, 29 Apr. 2022 When wet, the waste coal leaches acid into area waterways. Amy Beth Hanson, Chron, 22 Apr. 2022 When wet, the waste coal leaches acid into area waterways. Amy Beth Hanson, Anchorage Daily News, 21 Apr. 2022 Some acid, with just a bit of butterscotch on the finish. Marc Bona, cleveland, 13 Mar. 2022 Recent Examples on the Web: Adjective For all his gentility, Mr. Freed could be acid in his observations. Washington Post, 6 Jan. 2022 The painting was also damaged in an acid attack in the 1950s, according to the AP. Alison Fox, Travel + Leisure, 31 May 2022 It was also damaged in an acid attack perpetrated by a vandal in the 1950s, and has since been kept behind glass. Chron, 30 May 2022 Some users also reported less back and neck pain over time and improved sleeping experiences for those with acid reflux. Good Housekeeping, 12 May 2022 If acid green isn’t quite your style, consider a deeper, moodier shade, like this deep green in the Hudson, New York, home belonging to the founders of Perifio. Monique Valeris, ELLE Decor, 6 May 2022 His prodigious talents and ability to weave styles earned him the moniker as a grandfather of acid jazz. Lars Brandle, Billboard, 29 Sep. 2021 Further, some people with M.S. mistake symptoms of acid reflux, gastrointestinal conditions, and even anxiety as the M.S. hug. Sara Gaynes Levy, SELF, 19 Apr. 2022 Thompson adds a touch of sugar to his tomato sauce to help customers who suffer from acid reflux. Washington Post, 18 Apr. 2022 See More

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.

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

Learn More About acid

Dictionary Entries Near acid

aciculum

acid

acid alizarin red B

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Statistics for acid

Last Updated

29 Jun 2022

Cite this Entry

“Acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acid. Accessed 30 Jun. 2022.

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More Definitions for acid

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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