Definition of billon in English:



mass noun
  • An alloy formerly used for coinage, containing gold or silver with a predominating amount of copper or other base metal.

    • ‘By the 17th century the Polish influence was nearly complete, with a range of denominations from small billon coins to large gold multiple ducats.’
    • ‘The falling value of the Scottish currency derived in part from the practice of mixing silver with alloy to produce the base metal billon.’
    • ‘Our coin of Valerian II is clearly billon of the type used in the first years of the reign.’
    • ‘Numismatists of the 19th century, realizing the problems caused by the gaps in their knowledge, invented an arbitrary scale to refer to the bronze and billon coins of the period.’
    • ‘Large quantities of billon coins were produced in the Roman era, many with a silver wash, and in mediaeval times throughout Europe.’


Early 18th century: from French, literally ‘bronze or copper money’, in Old French ‘ingot’, from bille (see billet).