'maleic acid' definitions:

Definition of 'maleic acid'

(from WordNet)
noun
A colorless crystalline compound found in unripe fruit (such as apples or tomatoes or cherries) and used mainly to make polyester resins

Definition of 'maleic acid'

From: GCIDE
  • maleic acid \maleic acid\ n. (Chem.) An unsaturated dicarboxylic acid (HO.CO.CH=CH.CO.OH) of cis conformation, having various uses in the manufacture of artificial resins, the dyeing and finishing of wool, silk, and cotton, and also combined with certain drugs to make salts more soluble than the basic forms. The corresponding isomer having trans conformation, is identical in chemical formula, is called fumaric acid. --MI11 [PJC]