fumaric, a.
Pertaining to, or derived from, fumitory (Fumaria officinalis). [1913 Webster]
Fumaric acid (Chem.),
a widely occurring organic acid, extracted from fumitory as a white crystallline substance, C2H2(CO2H)2, and produced artificially in many ways, as by the distillation of malic acid; boletic acid. It is found also in the lichen, Iceland moss, and hence was also called lichenic acid.