butyl
Chemical term for the alkyl group C₄H₉. Used as a noun or prefix in compound names such as ブチルアルコール (butyl alcohol).
Butyl rubber has excellent oil resistance.
この化合物にはブチル基が含まれている。
This compound contains a butyl group.
butyl alcohol
Borrowed from English 'butyl', which derives from 'butyric acid' (from Latin butyrum 'butter') + '-yl'.