ozone

noun

ˈō-ˌzōn How to pronounce ozone (audio)
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
ozonic
ō-ˈzō-nik How to pronounce ozone (audio) -ˈzä- How to pronounce ozone (audio)
adjective

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.
These missions will provide dramatic views of the moon’s shadow from high above Earth while also measuring changes in atmospheric ozone, which depends on sunlight for its formation. — Jamie Carter, Forbes.com, 1 Aug. 2026 Care teams monitor daily weather and ozone alerts to tailor accommodations. — Kelly Werthmann, CBS News, 30 July 2026 Now imagine that on Tuesday, the nitrogen dioxide held at 105, while ozone levels dropped to 30. — Daniel Engber, The Atlantic, 24 July 2026 Air quality Unhealthful air quality is expected for inland valleys, the South Coast Air Quality Management District, which issued an ozone advisory for Thursday. — Alex Wigglesworth, Los Angeles Times, 23 July 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

Phrases Containing ozone

Rhymes for ozone

See All Rhymes for ozone

Browse Nearby Words

ozonation
ozone
ozone-friendly
See all Nearby Words

Cite this Entry

“Ozone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ozone. Accessed 7 Aug. 2026.

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Kids Definition

ozone

noun
ˈō-ˌzōn How to pronounce ozone (audio)
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

ozone

noun
ˈō-ˌzōn How to pronounce ozone (audio)
: 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
ozonic
ō-ˈzō-nik How to pronounce ozone (audio) -ˈzän-ik How to pronounce ozone (audio)
adjective

More from Merriam-Webster on ozone

Nglish: Translation of ozone for Spanish Speakers

Britannica.com: Encyclopedia article about ozone

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