Function of a faucet insert

• Exposure to air
• Soda-making process
• Ventilator's job
• The act of charging a liquid with a gas making it effervescent
• Purpose of a faucet attachment

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 .

Wiktionary Word definitions in Wiktionary
alt. The process by which air is circulated through or mixed with a substance such as soil or a liquid. n. The process by which air is circulated through or mixed with a substance such as soil or a liquid.

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 ...