from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. The univalent radical or group OH, a characteristic component of bases, certain acids, phenols, alcohols, carboxylic and sulfonic acids, and amphoteric compounds.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A univalent radical or functional group (–OH) in organic chemistry; present in alcohols, phenols, carboxylic acids and certain other classes of compounds.

from the GNU version of the Collaborative International Dictionary of English

  • n. A compound radical, or unsaturated group, HO, consisting of one atom of hydrogen and one of oxygen. It is a characteristic part of the hydrates, the alcohols, the oxygen acids, etc.

from The Century Dictionary and Cyclopedia

  • n. A compound radical (OH) which has never been isolated, but which is a factor in a vast number of chemical compounds.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. the monovalent group -OH in such compounds as bases and some acids and alcohols


from The American Heritage® Dictionary of the English Language, 4th Edition

hydr(o)- + ox(ygen) + -yl.


  • (SIMS), which allowed them to analyze the grains for a compound known as hydroxyl, which can be incorporated into apatite's chemical structure if the mineral crystallizes from magma that contains water.

    Christian Science Monitor | All Stories

  • Rather, coal power production and other industrial processes release sulfur dioxide -- the same gas that billows from volcanoes -- that later reacts with atmospheric molecules called hydroxyl radicals to produce sulfates as a byproduct. - latest science and technology news stories

  • As a former high school chemistry teacher, I would often teach my students about the dangers of dihydrogen monoxide or DHMO, also known as hydroxyl acid.

    Summit Daily News - Top Stories

  • Many studies have shown that trace gases and pollutants in the lowest level of our atmosphere break down naturally, thanks to molecules called hydroxyl (OH) radicals.

    National Geographic News

  • Methane is destroyed by reaction with an atmospheric "cleanser" called the hydroxyl free radical, or OH.


  • To the astronomers 'surprise, Spitzer picked up the signature of rapidly spinning fragments of water molecules, called hydroxyl, or OH.

    News and Features - NASA's Jet Propulsion Laboratory

  • Methane can be destroyed, however, by reactions involving an atmospheric "cleanser" called the hydroxyl free radical (OH).

    Climate Ark Climate Change & Global Warming RSS Newsfeed

  • NASA-engineered collision last year found a surprisingly rich mixture that, in addition to the silver, included water and compounds such as hydroxyl, carbon monoxide, carbon dioxide, ammonia, and free sodium. | Top Stories

  • When you want to hydrate your skin use a lotion which contains smooth-out ingredients such as hydroxyl acid or salicylic acid. New Blogs and RSS Feeds

  • Rebamipide is an anti-ulcer drug used to treat peptic ulcer, which has been demonstrated to enhance the production of endogenous prostaglandin E2 via COX-2 and thereby act as a gastric mucosal protectant, to promote mucin production, and to suppress the production of free radicals, such as hydroxyl radicals and superoxide ions.

    Health News from Medical News Today


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