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Medical Term:


Pronunciation: ār

Definition: A mixture of odorless gases found in the atmosphere in the following approximate percentages by volume after water vapor has been removed: oxygen, 20.95; nitrogen, 78.08; argon 0.93; carbon dioxide, 0.03; other gases, 0.01. Formerly used to mean any respiratory gas, regardless of its composition.

Synonym(s): ventilate

[G. aēr; L. aer]

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