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

/ ŏk′sĭ-jən /

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 Words From

ox·y·gen·ic [ok-si-, jen, -ik], ox·yg·e·nous [ok-, sij, -, uh, -n, uh, s], adjective
ox·y·gen·ic·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 oxygène, equivalent to oxy- + -gène; oxy- ¹, -gen

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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.

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Example Sentences

Sodium cyanide, which is used in industry including for metal cleaning, is a also a toxic substance and poisonous for living organisms as it disrupts cell function and leads to oxygen starvation.

From BBC

Campaigners warn that agricultural and sewage pollution combined with the impacts of climate change have led to algal blooms, starving wildlife of oxygen.

From BBC

The plant is rich in vitamins, minerals, calcium, iron, fiber, protein and calories; helps stimulate breathing and allows the lungs to absorb more oxygen, which is useful in the highlands of Bolivia.

From Salon

Palace's French striker was given oxygen before being taken to an ambulance and needed 25 stitches for a severe laceration to his left ear.

From BBC

A sweet moron, but a moron nonetheless, which is evident as soon as Pattinson starts squeaking banalities in a nasal gasp that sounds as though he’s never gotten enough oxygen to his brain.

From Los Angeles Times

OxyContin oxygen acid

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