a synthetic, white, crystalline powder, CHON, used as a drug to treat infections caused by various types of herpesviruses
See acyclovir in American Heritage Dictionary 4
(ā-sīˈklō-vîr, -klə-)
noun
A synthetic purine nucleoside analog, C8H10N5O3, derived from guanine and used in the treatment of herpes simplex, herpes zoster, and varicella zoster virus infections.