ozone

[ oh-zohn, oh-zohn ]

noun

1. a form of oxygen, O 3 , with a peculiar odor suggesting that of weak chlorine, produced when an electric spark or ultraviolet light is passed through air or oxygen. It is found in the atmosphere in minute quantities, especially after a thunderstorm, is a powerful oxidizing agent, and is thus biologically corrosive. In the upper atmosphere, it absorbs ultraviolet rays, thereby preventing them from reaching the surface of the earth. It is used for bleaching, sterilizing water, etc.

ozone

/ əʊˈzəʊn; əʊˈzɒnɪk; ˈəʊzəʊn /

noun

1. a colourless gas with a chlorine-like odour, formed by an electric discharge in oxygen: a strong oxidizing agent, used in bleaching, sterilizing water, purifying air, etc. Formula: O 3 ; density: 2.14 kg/m³; melting pt: –192°C; boiling pt: –110.51°C Technical nametrioxygen
2. informal.
   clean bracing air, as found at the seaside

ozone

/ ō′zōn′ /

1. An unstable, poisonous allotrope of oxygen having the chemical formula O 3 . Ozone forms in the atmosphere through the process of photolysis, when ultraviolet radiation from the Sun strikes oxygen molecules (O 2 ), causing them to split apart. When freed oxygen atoms bump into and join other O 2 molecules, they form ozone. Although ozone is broken down naturally in the atmosphere through chemical reactions with other atmospheric gases (such as nitrogen, hydrogen, and chlorine), in an unpolluted atmosphere the formation and breakdown of ozone is generally balanced, and the total concentration of ozone is relatively constant. The formation and destruction rates of ozone vary with altitude in the atmosphere, and with latitude. Most ozone forms in the 15 to 30 km (10 to 19 mi) altitude range and in latitudes closest to the equator where sunshine strikes the Earth the most. The ozone is then transported northward and southward by wind and is generally most concentrated in areas above the Canadian Arctic and Siberia and above Antarctica. Ozone is used commercially in water purification, in air conditioning, and as a bleach.

Derived Forms

• ozonic, adjective

Other Words From

• o·zon·ic [oh-, zon, -ik, oh-, zoh, -nik], adjective

Word History and Origins

Origin of ozone¹

< German Ozon < Greek ózōn, present participle of ózein to smell; ozo-

Word History and Origins

Origin of ozone¹

C19: from German Ozon, from Greek: smell

A Closer Look

Ozone is both beneficial for and threatening to all of Earth's organisms, including human beings, depending on how high in the atmosphere it is found. Ozone is naturally produced in the stratospheric portion of Earth's atmosphere (in the ozone layer) by the action of high-energy ultraviolet radiation on molecular oxygen (O 2 ). By absorbing much of the Sun's ultraviolet radiation, the ozone layer serves as a sunscreen for organisms on Earth. In recent years the ozone has thinned or disappeared in parts of the ozone layer, creating an ozone hole that lets in dangerous amounts of ultraviolet radiation. Ozone holes are caused in part by the release into the atmosphere of industrial and commercial chemicals, in particular the chlorofluorocarbons (such as freon) used in aerosols, refrigerants, and certain cleaning solvents. Closer to Earth's surface, ozone is one of the so-called greenhouse gases that are produced by the burning of fossil fuels and cause the greenhouse effect. Ozone at ground level is also an air pollutant, contributing to respiratory diseases such as asthma.

Example Sentences

If you start to lose hope, remember that young person and that we’ve beaten a climate problem before: the hole in the ozone layer.

From Los Angeles Times

Fine particulate matter can be the more damaging to people’s health than other pollutants, such as ozone.

From Los Angeles Times

An atmospheric chemist at MIT whose research was key to healing the giant gaping hole in our ozone layer, Solomon gives us much-needed inspiration — and some tangible ways forward.

From Los Angeles Times

The South Coast Air Quality Management District issues an air quality alert due to elevated fine particle pollution levels due to wildfire smoke and ozone pollution.

From Los Angeles Times

The South Coast Air Quality Management District has issued an air quality alert Monday due to elevated fine particle pollution levels because of the wildfire smoke and ozone air pollution.

From Los Angeles Times

Related Words

• atmosphere
• breeze
• wind