Toluene, formerly known as toluol, is a clear, water-insoluble liquid with the typical smell of paint thinners. Chemically it is a mono-substituted benzene derivative, i.e. one in which a single hydrogen atom from the benzene molecule has been replaced by a univalent group, in this case CH3. It is an aromatic hydrocarbon that is widely used as an industrial feedstock and as a solvent.
Toluene is a common solvent, able to dissolve paints, paint thinners, silicone sealants, many chemical reactants, rubber, printing ink, adhesives (glues), lacquers, leather tanners, and disinfectants.