oxygen

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noun, often attributive ox·y·gen \ˈäk-si-jən\

Definition of oxygen

  1. 1 :  a reactive element that is found in water, in most rocks and minerals, in numerous organic compounds, and as a colorless tasteless odorless diatomic gas constituting 21 percent of the atmosphere, that is capable of combining with all elements except the inert gases, that is active in physiological processes, and that is involved especially in combustion — see element table

  2. 2 :  something that sustains or fuels disagreement is the true oxygen of these magazines — Joseph Epstein

oxygenless

play \ˈäk-si-jən-ləs\ adjective

Recent Examples of oxygen from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'oxygen'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of oxygen

French oxygène, from Greek oxys, adjective, acidic, literally, sharp + French -gène -gen; akin to Latin acer sharp — more at edge

Other Chemical Engineering Terms


OXYGEN Defined for English Language Learners

oxygen

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noun

Definition of oxygen for English Language Learners

  • : a chemical that is found in the air, that has no color, taste, or smell, and that is necessary for life


OXYGEN Defined for Kids

oxygen

play
noun ox·y·gen \ˈäk-si-jən\

Definition of oxygen for Students

  1. :  a chemical element found in the air as a colorless odorless tasteless gas that is necessary for life

History for oxygen

People once thought that all acids were formed by adding oxygen to some other substance. This belief turned out not to be true. However, it did give oxygen its name. The first part of the word, oxy-, came from Greek oxys, meaning “acid” or “sharp.” The second part, -gen, came from a Greek element meaning “producing” or “giving rise to.”


Medical Dictionary

oxygen

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noun ox·y·gen \ˈäk-si-jən\

Medical Definition of oxygen

  1. :  a colorless tasteless odorless gaseous element that constitutes 21 percent of the atmosphere and is found in water, in most rocks and minerals, and in numerous organic compounds, that is capable of combining with all elements except the inert gases, that is active in physiological processes, and that is involved especially in combustion processes—symbol O; see element table

oxygenic

\ˌäk-si-ˈjen-ik\play adjective


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