n. A polycyclic aromatic hydrocarbon consisting of a benzene ring attached to each of the rings of a naphthalene molecule; it is carcinogenic, and is a product of incomplete combustion.
the GNU version of the Collaborative International Dictionary of English
n. A white crystalline hydrocarbon C15H10, of a complex structure, found as one ingredient of the higher boiling portion of coal tar.
The Century Dictionary and Cyclopedia
n. A solid hydrocarbon, C15 H10, found in coal-tar, in American petroleum, and in the organic distillate obtained in the preparation of mercury from its ores in Idria, whence its other name, idryl. It melts at 110° C.
Word Usage
"The earthworms and nematodes are being exposed to a variety of toxins and chemicals including cadmium, copper, atrazine, fluoranthene and the insecticide aldicarb."