Medical Dictionary
usnic acid
noun us·nic acid \ˌəs-nik-\
Medical Definition of USNIC ACID
: a yellow crystalline antibiotic C18H16O7 that is obtained from various lichens (as old-man's beard)
Seen & Heard
What made you want to look up usnic acid? Please tell us where you read or heard it (including the quote, if possible).