oxygen
Americannoun
noun
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A nonmetallic element that exists in its free form as a colorless, odorless gas and makes up about 21 percent of the Earth's atmosphere. It is the most abundant element in the Earth's crust and occurs in many compounds, including water, carbon dioxide, and iron ore. Oxygen combines with most elements, is required for combustion, and is essential for life in most organisms. Atomic number 8; atomic weight 15.9994; melting point −218.8°C; boiling point −182.9°C; gas density at 0°C 1.429 grams per liter; valence 2.
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See Periodic Table
Word History
In 1786, the French chemist Antoine Lavoisier coined a term for the element oxygen (oxygène in French). He used Greek words for the coinage: oxy– means “sharp,” and –gen means “producing.” Oxygen was called the “sharp-producing” element because it was thought to be essential for making acids. Lavoisier also coined the name of the element hydrogen, the “water-producing” element, in 1788. Soon after, in 1791, another French chemist, J. A. Chaptal, introduced the word nitrogen, the “niter-producing” element, referring to its discovery from an analysis of nitric acid.
Discover More
Oxygen is a waste product of green plants and photosynthesis.
When we breathe in oxygen, it is carried by the hemoglobin in our blood throughout the body, where it is used to generate energy by oxidation. (See respiration.)
Other Word Forms
- oxygenic adjective
- oxygenicity noun
- oxygenous adjective
Etymology
Origin of oxygen
First recorded in 1780–90; from French oxygène, equivalent to oxy- + -gène; oxy- 1, -gen
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.
Several explosions from exploding oxygen canisters within the ambulances caused windows of nearby buildings, including the synagogue to crack or shatter - however no injuries were reported.
From BBC
The tubing running from the oxygen tank behind him to his nose jostles around and he readjusts it, setting it back in its proper place.
From Literature
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Using JWST, the team measured emissions from O III, an ionized form of oxygen that signals recent star formation.
From Science Daily
It not only provides drinking water, but can also be split into hydrogen and oxygen to provide air for astronauts to breathe, and even fuel for spacecraft.
From BBC
Blood vessels deliver oxygen and nutrients needed to generate heat and help distribute that heat throughout the body.
From Science Daily
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.