Trichlorobenzene

Part of speech: noun

Definitions

1. Any of several colorless aromatic compounds made from benzene with three chlorine atoms attached to its ring, used as solvents and chemical intermediates
2. A chlorinated hydrocarbon in which three hydrogen atoms of benzene have been replaced by chlorine, used industrially as a solvent and in making other chemicals
3. An organic chemical formed by substituting three chlorine atoms for hydrogen on a benzene ring, employed in manufacturing and as a heat-transfer fluid

Etymology: Trichlorobenzene is a systematic chemical name, built by stacking standard chemistry prefixes onto a base word. "Benz-" comes from benzoin, the resin from which benzoic acid was first obtained, and the "-ene" ending marks a hydrocarbon with a ring of unsaturated carbon atoms. "Tri-" means three and "chloro-" refers to chlorine, so the name describes benzene with three chlorine atoms substituted onto its ring. Because the ring can carry the chlorine atoms in different positions, there are three distinct compounds with this formula: 1,2,3-, 1,2,4- and 1,3,5-trichlorobenzene. Chemists distinguish them by numbering the ring carbons, so the bare word covers a family of isomers rather than a single substance.