Definition of fusain in English:

fusain

noun

Geology
  • A crumbly, porous type of coal resembling wood charcoal, used in drawing.

    • ‘The conglomerate is overlain by a claystone-dominated fossiliferous interval, which contains spirorbid worm tubes, abundant conchostracans, plant debris, fusain, and a pygocephalomorph-bearing limestone.’
    • ‘Minor amounts of fusain also occur in association with the fossils.’
    • ‘In nearly all cases, fusain had the largest ratio of C-C bonds.’
    • ‘As an independent check on the overall oxygen trend, it is notable that fusain is found for the first time in the Late Devonian.’
    • ‘Forest fire, a major disturbance agent in some modern forests, does not appear to be a major factor given the rarity of fusain in the Buchanan Lake Formation deposits.’

Origin

Late 19th century: from French, literally spindle tree also fine charcoal (made from the spindle tree).

Pronunciation:

fusain

/ˈfyo͞ozān/