hy·​drox·​yl | \ hī-ˈdräk-səl How to pronounce hydroxyl (audio) \

Definition of hydroxyl

1 : the chemical group, ion, or radical OH that consists of one atom of hydrogen and one of oxygen and is neutral or negatively charged

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Other Words from hydroxyl

hydroxylic \ ˌhī-​ˌdräk-​ˈsi-​lik How to pronounce hydroxylic (audio) \ adjective

Examples of hydroxyl in a Sentence

Recent Examples on the Web As a result, one of every four water molecules has something akin to a grasping limb—a single hydroxyl (OH) group—pointing up into the air with nothing to bind to, creating an uneven chemical landscape. Emily Underwood, Smithsonian Magazine, "The Complicated Role of Iron in Ocean Health and Climate Change," 3 Jan. 2020 Sharpe has begun lending his stock of hydroxyl generators, which use ultraviolet light to kill microorganisms in the air, to local hospitals and homes for the elderly, where many are particularly vulnerable to COVID-19, the coronavirus disease. Chase Difeliciantonio, SFChronicle.com, "Workplace cleanliness a critical issue for businesses still operating in coronavirus era," 28 Mar. 2020 However, later observations of the surface made with Chandrayaan-1, NASA's Cassini spacecraft, and NASA's Deep Impact probe called that assumption into question after detecting the spectral signal of either water or the hydroxyl group. Fox News, "5 interesting facts about the moon," 16 Mar. 2020 Rather, the hydroxyl groups, which are created by a reaction between HIF-1 alpha and oxygen, mark it for destruction by a cell’s protein-degrading machinery. The Economist, "Batteries, exoplanets, cosmology and cell biology win Nobel laurels," 12 Oct. 2019 Without hydroxyl, certain substances humans rely on, such as sugars and alcohols, would not exist. Peter Fimrite, SFChronicle.com, "Planned trips to moon could usher in space-based commerce," 8 June 2019 Those investigations led to a discovery a couple of years later involving the reactive oxygen species (ROS) — unstable molecules containing oxygen, such as peroxides, singlet oxygen and hydroxyl radicals — that mitochondria release while making ATP. Quanta Magazine, "Biologists Discover Unknown Powers in Mighty Mitochondria," 18 Mar. 2019 Typically cleansers with beta hydroxy acids, like salicylic, and alpha hydroxyl acids, like glycolic and lactic, are marketed to teens and those who suffer from acne (so perfect if your discoloration comes from pimples). Alexandra Engler, Marie Claire, "From Topical Treatments to Lasers, Your Complete Guide to Treating Dark Spots," 7 Mar. 2017 Salicylic acid = a beta hydroxyl acid from the bark of a willow tree. Lori Keong, Marie Claire, "How to Get Rid of Rogue Pimples Overnight," 3 Mar. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hydroxyl.' 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 hydroxyl

1869, in the meaning defined at sense 1

History and Etymology for hydroxyl

hydr- + ox- + -yl

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Time Traveler for hydroxyl

Time Traveler

The first known use of hydroxyl was in 1869

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Statistics for hydroxyl

Cite this Entry

“Hydroxyl.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydroxyl. Accessed 24 Oct. 2020.

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More Definitions for hydroxyl


hy·​drox·​yl | \ hī-ˈdräk-səl How to pronounce hydroxyl (audio) \

Medical Definition of hydroxyl

1 : the chemical group or ion OH that consists of one atom of hydrogen and one of oxygen and is neutral or positively charged

Other Words from hydroxyl

hydroxylic \ ˌhī-​ˌdräk-​ˈsil-​ik How to pronounce hydroxylic (audio) \ adjective

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