Wiktionary
tricarboxylic acid
n. (context organic chemistry English) An organic carboxylic acid whose chemical structure contains three carboxyl functional groups, the best-known example being citric acid.
Wikipedia
Tricarboxylic acid
A tricarboxylic acid is an organic carboxylic acid whose chemical structure contains three carboxyl functional groups (-COOH). The best-known example of a tricarboxylic acid is citric acid.