acid

noun

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 7a) 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
ac·id | \ˈa-səd \

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

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

Climate change is turning our oceans into globe-spanning acid baths. Ryan Smith, Chicago Reader, "Free Shit / Music Guess who’s on our cover for a chance to win passes to the 2018 Pitchfork Music Festival," 13 July 2018 The acid is perfect to cut through the fat and bread. Paula Forbes, GQ, "What to Drink With Your Burgers This Summer," 30 June 2018 Instead of or in conjunction with vinegar, citrus juice can also serve as the acid in a dressing. Becky Krystal, chicagotribune.com, "How to leave those bottled dressings behind and make your own vinaigrette," 29 June 2018 These cells produce a basic mucus that neutralizes the acid in your stomach. Megan Arnett, Scientific American, "Sweet and Sour Science You Can Taste!," 21 June 2018 Studies show that the acid contained in bile does have medical benefits in dissolving gallstones or treating some liver disease, as well as some anti-inflammatory and antimicrobial properties. Author: Simon Denyer, Anchorage Daily News, "From hemorrhoids to hangovers: Bear bile is treasured in China, and that’s bad for captive bears," 3 June 2018 Studies show that the acid contained in bile does have medical benefits in dissolving gallstones or treating some liver disease, as well as some anti-inflammatory and antimicrobial properties. Simon Denyer, Washington Post, "China’s bear bile industry persists despite growing awareness of the cruelty involved," 3 June 2018 And the acid and herbs in the salad combine with the creaminess of the yogurt to cover the rest of the bases. Alex Delany, Bon Appetit, "My 100% Hypothetical Fantasy Cookout," 25 May 2018 The acid in the vinegar should break down the black junk. Heloise, Houston Chronicle, "The weight makes the eggs," 23 May 2018

Recent Examples on the Web: Adjective

Start this intense 30 percent acid peel as a single daily treatment, and after a few days, try your hand at a morning and evening application for glowy and clear skin at warp speed. Ashley Weatherford, The Cut, "Are You Exfoliating Your Face Wrong?," 11 July 2018 This coffee has an acid taste John Lennon and George Harrison's first experience with LSD was in April 1965, when Harrison's dentist slipped it into their after-dinner coffee, unbeknownst to them. John Harrington And Charles Stockdale, USA TODAY, "50 fascinating facts you may not know about The Beatles," 10 July 2018 There was just enough cheese to add its satisfying umami without being heavy, and the tomato sauce, quickly cooked, was the perfect sweet-acid component to balance the fried eggplant slices. Evan Kleiman, latimes.com, "Cucina Italiana: The joy of eggplant. Try making a timbale," 5 July 2018 The two men who allegedly made two acid bombs Tuesday at a home just outside Baldwin Park wanted to scare off some unwanted guests, an affidavit says. David Harris, OrlandoSentinel.com, "Men made acid bombs to scare unwanted occupants at Baldwin Park-area home, affidavit says," 7 June 2018 Whether sending up the New York art world or hanging out with acid heads, Wolfe inevitably presented man as a status-seeking animal, concerned above all about the opinion of one’s peers. Hillel Italie, BostonGlobe.com, "Tom Wolfe, pioneering ‘New Journalist,’ dies at 88," 15 May 2018 Shallots will tolerate all but the most acid soils, but dig the earth deeply because the plants put down 8-inch-long feeder roots. The Editors Of Organic Life, Good Housekeeping, "How To Grow Onions," 1 Feb. 2018 The overall effect is a film that—flaws and all—marries acid satire and a trippy futurescape where oppression is the norm to an ethos of genuine hope. Vann R. Newkirk Ii, The Atlantic, "Sorry to Bother You Is a Dystopian Send-Up of Dystopias," 13 July 2018 Click to Read Story A Surprise Medical Solution: Hypnosis Major hospitals are finding hypnotherapy can help sufferers of digestive conditions like heartburn, acid reflux and irritable bowel syndrome. Sumathi Reddy, WSJ, "From Meditation to Medication: Headspace Has a Prescription Strategy," 25 June 2018

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

Phrases Related to acid

acid indigestion

drop acid

Statistics for acid

Last Updated

15 Oct 2018

Look-up Popularity

Time Traveler for acid

The first known use of acid was in 1649

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More Definitions for acid

acid

adjective

English Language Learners Definition of acid

 (Entry 1 of 2)

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

: sharp, strong, and critical in tone

acid

noun

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

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

acid

adjective
ac·id | \ˈa-səd \

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 \

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

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Comments on acid

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