1
: a triatomic very reactive form of oxygen that is a bluish irritating gas of pungent odor, that is a major air pollutant in the lower atmosphere but a beneficial component of the upper atmosphere, and that is used for oxidizing, bleaching, disinfecting, and deodorizing
2
: pure and refreshing air
relished the ozone of morning

Examples of ozone in a Sentence

Scientists are concerned about ozone depletion. A light breeze filled the rooms of our seaside cottage with ozone.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The amount of ozone in the atmosphere can fluctuate through the year, and October is typically the month in which there is the least ozone. Adam Kovac, Scientific American, 16 Sep. 2026 Rather than filtering contaminants out and concentrating them into waste, this method uses ozone gas and naturally occurring microbes to break contaminants down instead of just isolating them. Piper Heath, Los Angeles Times, 16 Sep. 2026 There are more stringent ozone standards that are still not being met, and the district is hoping to reach those levels within the next six years. James Taylor, CBS News, 10 Sep. 2026 During alerts, the district advises limiting outdoor exercise to the early morning hours, when ozone concentrations are lower. Jason Green, Mercury News, 8 Sep. 2026 See All Example Sentences for ozone

Word History

Etymology

German Ozon, from Greek ozōn, present participle of ozein to smell — more at odor

First Known Use

1840, in the meaning defined at sense 1

Time Traveler
The first known use of ozone was in 1840

Browse Nearby Words

Cite this Entry

“Ozone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ozone. Accessed 23 Sep. 2026.

Kids Definition

1
: a form of oxygen that is a bluish irritating sharp-smelling gas containing three atoms per molecule, and that is used especially in disinfecting, deodorizing, and bleaching
2
: pure and refreshing air

Medical Definition

: a triatomic very reactive form of oxygen that is a bluish irritating gas of pungent odor, that is formed naturally in the atmosphere by a photochemical reaction and is a major air pollutant in the lower atmosphere but a beneficial component of the upper atmosphere, and that is used for oxidizing, bleaching, disinfecting, and deodorizing

More from Merriam-Webster on ozone

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