specifically: any of various typically water-soluble and sour compounds that in solution are capable of reacting with a base (see baseentry 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
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
If your skin is looking a little dull, these two products will brighten up your complexion à la tranexamic acid, niacinamide, and lotus seed extract (SkinMedica) or L-ascorbic acid and hyaluronic acid (Obagi Medical).—Sarah Han, Allure, 28 Nov. 2023 The two-step anti-aging AHA/BHA pad is pre-dosed with five acids to visibly reduce dullness, uneven texture, pores and dark spots.—Anna Tingley, Variety, 24 Nov. 2023 In interviews, some city sanitation workers described persistent safety concerns, such as coming into contact with carcasses of rabid dogs and acid splatter from batteries.—Kurtis Lee, New York Times, 23 Nov. 2023 Its formula is made with patented Resorcinol Technology, glycolic acid, and tranexamic acid, which all work together to reduce dark spots and discoloration and brighten the skin in just 14 days.—Rachel Simon, Peoplemag, 17 Nov. 2023 This production emphasizes — overly, in some places — the acid suspended in those charming rhymes.—Jackson McHenry, Vulture, 31 Oct. 2023 Red onion and tomatoes provide acid while a sprinkling of cilantro freshens up what would otherwise be a heavy — and massive — taco.—Kat Thompson, Los Angeles Times, 25 Oct. 2023 Antacids work by neutralizing stomach acid, while PPIs and H2 blockers reduce the amount of acid the stomach makes.—Maggie O'Neill, Health, 16 Nov. 2023 Some grapes have naturally longer lifespans due to tannic structure and acid levels; in general, Cabernet Sauvignon has greater longevity than Pinot Noir.—Mike Desimone and Jeff Jenssen, Robb Report, 5 Nov. 2023
Peptic ulcers occur when acid in the digestive tract eats away at the inner surface of the stomach or small intestine, according to the Mayo Clinic.—Nardine Saad, Los Angeles Times, 7 Sep. 2023 Given that, acid chemical rust removers are best limited to removing rust from bare iron and steel.—Tony Carrick, Popular Mechanics, 23 Mar. 2023 High levels of protein can increase acid production in urine, potentially leading to stone formation.—Amber Smith, Discover Magazine, 10 Aug. 2023 For people with chronic acid reflux symptoms, healthcare providers may recommend PPIs for longer than 12 weeks.—Maggie O'Neill, Health, 22 Aug. 2023 And while diet changes can help, Lakshminarayan told CNN that people suffering from acid reflux and heartburn should seek medical care.—Cara Lynn Shultz, Peoplemag, 10 Aug. 2023 From the mountains and acid soils of the east to the inner Bluegrass to the western waterlands.—Paul Cappiello, The Courier-Journal, 16 June 2023 Pressure canning uses steam to create high temperatures that kill microorganisms and pressure to seal jars filled with low acid foods like chicken stock or baked beans.—Jonathan Bender, Popular Mechanics, 4 Aug. 2023 Acid Reflux When burping goes hand-in-hand with heartburn, acid reflux may be to blame.—Karen Pallarito, Health, 27 July 2023 See More
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'acid.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
borrowed from Medieval Latin acidum, going back to Latin, neuter of acidusacid entry 2
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
specifically: any of various typically water-soluble and sour compounds that in solution are capable of reacting with a base (see basesense 3a) 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