Possible Definitions:
1. Drug (v. i.) To drudge; to toil laboriously.
2. Drug (n.) A drudge (?).
3. Drug (n.) Any animal, vegetable, or mineral substance used in the composition of medicines; any stuff used in dyeing or in chemical operations.
4. Drug (n.) Any commodity that lies on hand, or is not salable; an article of slow sale, or in no demand.
5. Drug (v. i.) To prescribe or administer drugs or medicines.
6. Drug (v. t.) To affect or season with drugs or ingredients; esp., to stupefy by a narcotic drug. Also Fig.
7. Drug (v. t.) To tincture with something offensive or injurious.
8. Drug (v. t.) To dose to excess with, or as with, drugs.