Definition of butyl in English:



  • 1[as modifier] An alkyl radical —C₄H₉, derived from butane.

    ‘butyl acetate’
    • ‘The subcommittee is currently reviewing two bills concerning methyl tertiary butyl ether.’
    • ‘The most durable exterior house paints are based on acrylic co-polymers of materials like methyl methacrylate and butyl acrylate.’
    • ‘These may contain solvents such as toluene, isopropryl alcohol, ethyl and butyl acetates, acetone and other ketones.’
    • ‘However, in Philadelphia, refineries had reformulated gasoline to include increased concentrations of methyl tertiary butyl ether.’
    • ‘These reformulated gasolines contain either corn-derived ethanol or natural-gas derivatives such as MTBE (methyl tertiary butyl ether).’
    1. 1.1
      short for butyl rubber
      • ‘Good ventilation, goggles, and butyl or nitrile rubber gloves are essential; work in a hood is recommended.’
      • ‘Several types of synthetic materials also may be referred to as latex (eg, butyl, petroleum-based materials) but these do not contain the proteins that cause allergic reactions.’
      • ‘Because no appropriate regulations existed in 1969, there was no legal requirement to line the landfill site in order to prevent leakage, thus no butyl membrane was ever applied to the base of the site, as would be the requirement nowadays.’
      • ‘Seam problems were resolved by the introduction of butyl seam tapes as a replacement for earlier liquid-applied neoprene adhesive.’
      • ‘I made this last year and the inside of it is a children's plastic sand pit with a butyl liner over it inside a timber frame.’


Mid 19th century: from butyric acid + -yl.