hydroxyl

noun

hy·​drox·​yl hī-ˈdräk-səl 

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

2

: hydroxide sense 1

hydroxylic

ˌhī-ˌdräk-ˈsi-lik 

adjective

Examples of hydroxyl in a Sentence

Recent Examples on the Web

Previous studies have revealed that protons from the solar wind that bombards the moon can absorb electrons from materials at its surface, forming atomic hydrogen that then reacts with oxygen atoms from silicate rocks to make hydroxyl—a molecule just one hydrogen atom short of water. —Leonard David, Scientific American, 26 Oct. 2020

Those measurements focused on a shorter, three-micron wavelength that was more ambiguous, unable to differentiate between a water molecule, which consists of two hydrogen atoms and one oxygen atom or hydroxyl, which has one hydrogen atom and one oxygen atom. —Kenneth Chang, New York Times, 26 Oct. 2020

The goal of this latest expedition, which is scheduled to return mid-February, is to see whether concentrations of an atmospheric molecule called hydroxyl, or OH, has changed over time since the industrial revolution. —Anna Funk, Discover Magazine, 7 Nov. 2018

During photocatalysis, light is absorbed by photocatalysts that have the ability to create electron-hole pairs, which generate free hydroxyl radicals that are able to react with target pollutants and degrade them. —IEEE Spectrum, 23 Jan. 2023

Word History

Etymology

hydr- + ox- + -yl

First Known Use

1869, in the meaning defined at sense 1

Kids Definition

hydroxyl

noun

hy·​drox·​yl hī-ˈdräk-səl 

: a chemical group or ion that consists of one atom of hydrogen and one of oxygen

Medical Definition

hydroxyl

noun

hy·​drox·​yl hī-ˈdräk-səl 

1

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

2

: hydroxide sense 1

hydroxylic

ˌhī-ˌdräk-ˈsil-ik 

adjective