acid

noun

\ ˈa-səd

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 Synonyms More Example Sentences Phrases Containing acid Learn More About acid

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

Recent Examples on the Web: Noun One more unexpected guest, however, was pro skater Tony Hawk, who rocked the front row in a Dior logo sweater and acid-wash jeans. — Christian Allaire, Vogue, 20 May 2022 However, cleanup costs for acid mine drainage remain prohibitive — requiring the construction of water treatment plants and operating them over years and decades. — Austyn Gaffney, Washington Post, 19 May 2022 What it's made of: This tall 15-inch latex mattress uses a quilted organic cover that's made with wool and polylactic acid (PLA) over an organic cotton pillowtop. — Grace Wu, Good Housekeeping, 18 May 2022 For a punch of acid and tartness, some kind of fruit is essential. — Kyle Beechey, Bon Appétit, 17 May 2022 Treatments have so far included lasers, over-the-counter topical products with ingredients such as sulfur and azelaic acid, and oral medication to reduce or soothe the symptoms. — Allure, 16 May 2022 Backed by a pop-art R&B revue, Sue strutted the stage in a bodysuit that looked like a good acid-trip. — Matt Wake | Mwake@al.com, al, 16 May 2022 Hyaluronic acid and wheat protein are also included in this formulation, which work to lock in moisture and improve hair elasticity, thereby decreasing the chance of breakage due to daily hair stressors. — Grooming Playbook, The Salt Lake Tribune, 16 May 2022 Gastroesophageal reflux disease, where stomach acid goes into the esophagus, is a much more common entity to cause heartburn and cough (this can be complicated because GERD is a common trigger for DES). — Dr. Keith Roach, oregonlive, 6 May 2022 Recent Examples on the Web: Adjective 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 The track’s resonant chords, crashing hi-hats and unraveling acid synth lead come to a boil beneath Diamond’s call for love, unity and a return to the music. — Billboard Staff, Billboard, 8 Apr. 2022 Those who work 12 hours each day tend to have an acid sense of humour. — Pablo Sandoval, Variety, 19 Mar. 2022 Kepler-22b has a native population of primitive humanoids who live underground and beneath an acid sea. — James Poniewozik, New York Times, 17 Mar. 2022 Floral in the nose, lime, more acid, greener fruit, slightly grassy but not as cloying as an Australian or New Zealand Sauv Blanc. — Marc Bona, cleveland, 13 Mar. 2022 If needed, fertilize rhododendrons, camellias and azaleas with acid-type fertilizer. — oregonlive, 1 Mar. 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.

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

Statistics for acid

Last Updated

24 May 2022

Cite this Entry

“Acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acid. Accessed 26 May. 2022.

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More Definitions for acid

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

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