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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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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Other Word Forms

oxygenic adjective
oxygenous adjective
oxygenicity 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 truth is that healthy oceans are essential to all life on earth. They generate half of the world's oxygen, regulate our climate and provide food for more than three billion people," he said.

From

“I’m sure they will at some point,” she says of the songs, both of which tend to take up all the available oxygen in a room.

From

In these recordings, you can hear the back-and-forth chatter, along with the astronaut’s breathing and the background noise of their spacesuit pumping oxygen into their helmet to keep them alive.

From

Wynter died from a loss of oxygen flow to her brain which could have been prevented had staff delivered her earlier.

From

“The same comet also has molecular oxygen in it, right?” he countered.

From

OxyContin oxygen acid

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