Answer: chark

AnswerCrossword Clue
charkto char (to scorch (to burn slightly))
charkthe solid product resulting from the destructive distillation of coal in an oven or closed chamber or by imperfect combustion, consisting principally of carbon: used chiefly as a fuel in metallurgy to reduce metallic oxides to metals
charkthe carbonaceous material obtained by heating wood or other organic substances in the absence of air
charkto char; convert into coke