Origin: Greek prefix anti-
Antiviral has 4 different meanings across 2 categories:
any drug that destroys viruses
"The doctor prescribed a new antiviral medication to destroy the severe virus causing his flu-like symptoms."
An antiviral medication.
"The doctor prescribed an antiviral to help me recover from the flu."
inhibiting or stopping the growth and reproduction of viruses
"The doctor prescribed an antiviral medication to stop the virus from multiplying inside his body before it spread further."
Inhibiting the growth and reproduction of a virus.
"The new medication is highly effective at stopping the replication of the flu virus before symptoms even begin."