Aeration

n. process of charging a liquid with a gas; process of exposing to the effect of air (as in oxygenating blood)

Aeration is the process by which air is circulated through, mixed with or dissolved in a liquid or substance.
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Noun
1. the process of exposing to air (so as to purify)
(hypernym) natural process, natural action, action, activity
(derivation) air out, air, aerate
2. the act of charging a liquid with a gas making it effervescent
(hypernym) change of state
(derivation) oxygenate, oxygenize, oxygenise, aerate

(n.)
The act or preparation of charging with carbonic acid gas or with oxygen.
  

(n.)
Exposure to the free action of the air; airing; as, aeration of soil, of spawn, etc.
  

(n.)
A change produced in the blood by exposure to the air in respiration; oxygenation of the blood in respiration; arterialization.
  

A process which promotes biological degradation of organic matter in water. The process may be passive (as when waste is exposed to air), or active (as when a mixing or bubbling device introduces the air).