from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A white or tan powder, C10H5Cl7, formerly used as a pesticide, that is highly toxic to humans and is a suspected carcinogen.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An organochlorine compound formerly used as an insecticide.
hepta- + chlor(ine).(American Heritage® Dictionary of the English Language, Fourth Edition)