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hydroxyl

American  
[hahy-drok-suhl] / haɪˈdrɒk səl /
Or hydroxy

adjective

  1. containing the hydroxyl group.


hydroxyl British  
/ haɪˈdrɒksɪl /

noun

  1. (modifier) of, consisting of, or containing the monovalent group -OH or the ion OH

    a hydroxyl group or radical

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

hydroxyl Scientific  
/ hī-drŏksĭl /
  1. The group OH. Hydroxyl is present in bases, certain acids, hydroxides, and alcohols.


Other Word Forms

Etymology

Origin of hydroxyl

First recorded in 1865–70; hydr- 2 + ox(y)- 2 + -yl

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Traditional CDT uses these tumor conditions to spark the formation of hydroxyl radicals, highly reactive molecules made of oxygen and hydrogen that contain an unpaired electron.

From Science Daily Mar. 1, 2026

This structure is capable of producing both hydroxyl radicals and singlet oxygen, increasing its cancer-fighting potential.

From Science Daily Mar. 1, 2026

Identifying water through its ultraviolet byproduct, hydroxyl, marks an important step in understanding how interstellar comets behave and change over time.

From Science Daily Feb. 11, 2026

Throughout the process, Huml also uses a variety of machines to clean the air, including air scrubbers, deodorizing hydroxyl generators and negative air machines that clean the air and push it outside.

From Los Angeles Times Jan. 16, 2025

Similarly, the replacement of hydrogen by a water-residue, hydroxyl, gives rise to a phenol.

From Coal and What We Get from It by Raphael Meldola

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