oxygen

[ ok-si-juhn ]

Phonetic (Standard)IPA

noun

Chemistry.

a colorless, odorless, gaseous element constituting about one-fifth of the volume of the atmosphere and present in a combined state in nature. It is the supporter of combustion in air and was the standard of atomic, combining, and molecular weights until 1961, when carbon 12 became the new standard. : O; : 15.9994; : 8; density: 1.4290 grams/liter at 0°C and 760 millimeter pressure.

oxygen

/ ɒkˈsɪdʒɪnəs; ˌɒksɪˈdʒɛnɪk; ˈɒksɪdʒən /

noun

1. a colourless odourless highly reactive gaseous element: the most abundant element in the earth's crust (49.2 per cent). It is essential for aerobic respiration and almost all combustion and is widely used in industry. Symbol: O; atomic no: 8; atomic wt: 15.9994; valency: 2; density: 1.429 kg/m³; melting pt: –218.79°C; boiling pt: –182.97°C
2. ( as modifier )
  an oxygen mask

oxygen

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.
See Periodic Table

oxygen

An element , normally a gas , that makes up about one-fifth of the atmosphere of the Earth . Oxygen is usually found as a molecule made up of two atoms . Its symbol is O.

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Notes

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 .)

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Derived Forms

oxygenic, adjective

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Other Word Forms

�ǳ�·��·��·�� [ok-si-, jen, -ik], �ǳ�·�ⲵ·��·�Դǳܲ� [ok-, sij, -, uh, -n, uh, s], adjective
�ǳ�·��·��·��·i·ty [ok-si-j, uh, -, nis, -i-tee], noun

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Word History and Origins

Origin of oxygen¹

First recorded in 1780–90; from French �ǳ�ⲵè�Ա�, equivalent to oxy- + -��è�Ա�; oxy- ¹, -gen

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Word History

In 1786, the French chemist Antoine Lavoisier coined a term for the element oxygen ( �ǳ�ⲵè�Ա� in French). He used Greek words for the coinage: �ǳ��– means “sharp,” and –g�� 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.

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Example Sentences

Examples have not been reviewed.

The Pope was breathing on his own, without oxygen tubes, despite being told by his doctors to spend two months convalescing after 38 days in hospital with double pneumonia.

From

Perhaps most amazingly, they are able to — apparently — die for a little while when ambient oxygen levels are extremely low, or completely absent.

From

It’s a high-tech twist on the classic mason jar, using a silicone lid with a degassing valve and an AirGone Argon Gas Canister to flush out oxygen.

From

Isaiah suffered "catastrophic" brain damage after being deprived of oxygen at birth and died in March 2018.

From

She also ordered oxygen canisters from Amazon for "respiratory support".

From

OxyContin oxygen acid

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