The process of exposing to air (so as to purify)

• Exposure to air
• Carbon dioxide treatment
• Ventilator's job
• Function of a faucet insert
• Soda-making process

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
aeration \aer*a"tion\, Aeration \A`["e]r*a"tion\, n. [Cf. F. a['e]ration.] Exposure to the free action of the air; airing; as, a["e]ration of soil, of spawn, etc. (Physiol.) A change produced in the blood by exposure to the air in respiration; oxygenation ...

Wikipedia Word definitions in Wikipedia
Aeration (also called aerification ) is the process by which air is circulated through, mixed with or dissolved in a liquid or substance.

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
1570s, from French aération , from aérer (v.), from Latin aer (see air (n.1)). In some cases, from aerate .