noun
de-aired water; deaerated water
Technical term for water from which dissolved gases (especially oxygen) have been removed, used in industrial, laboratory, or boiler contexts.
ボイラーには脱気水を使うことで腐食を防げる。
Using deaerated water in the boiler can prevent corrosion.
実験では脱気水を用いて溶存酸素の影響を除いた。
In the experiment, de-aired water was used to eliminate the effect of dissolved oxygen.
蒸留水 is distilled water, which may or may not be deaerated; 脱気水 focuses on gas removal, not necessarily distillation.
Compound of 脱気 (degassing, removal of gas) and 水 (water). The exact historical derivation is uncertain, but the term is a straightforward technical coinage.