Anoxia
Overview
 
The term anoxia means a total decrease in the level of oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

, an extreme form of hypoxia or "low oxygen". The terms anoxia and hypoxia are used in various contexts:
 
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