vermicide

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A substance or agent used to kill worms, especially parasitic worms.

from The Century Dictionary.

• noun A worm-killer; that which destroys worms: applied to those anthelmintic drugs which act by killing, and not simply expelling, parasitic worms, such as entozoans.

from the GNU version of the Collaborative International Dictionary of English.

• noun A medicine which destroys intestinal worms; a worm killer.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Any substance used to kill worms, especially parasitic intestinal worms

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an agent that kills worms (especially those in the intestines)