fumaric : Idioms & Phrases

• noun a colorless crystalline acid with a fruity taste; used in making polyester resins
  

WordNet

• (Chem.), a widely occurring organic acid, exttracted 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.

Webster 1913