[¦nī·trə·lō‚trī·ə′sēd·ik ′as·əd] (organic chemistry) N(CH2COOH)3 A white powder, melting point 240°C, with some decomposition; soluble in water; it is toxic, and birth abnormalities may result from ingestion; may be used as a chelating agent in the laboratory. Also known as NTA; TGA.AcronymsSeeNTA