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English definition of “oxygen”

oxygen

noun [U] uk   /ˈɒk.sɪ.dʒən/ us    /ˈɑːk-/ (symbol O)
B2 a chemical element that is a gas with no smell or colour. Oxygen forms a large part of the air on Earth, and is needed by animals and plants to live.Chemical elements
(Definition of oxygen from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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