Xylene - An aromatic hydrocarbon used as a common industrial solvent, also named dimethylbenzene; exists as 3 isomers: m-xylene, o-xylene, and p-xylene. Xylene is usually obtained from petroleum and natural gas distillates. It is used in paint, rubber and leather industries, and also as a cleaning agent or degreaser.
[Atmospheric Environment, v. 33, Issue 7, p. 1085-1092] 
Atmospheric Chemistry Glossary