ri·ba·vi·rin 
(rībə-vī′rĭn)
(rībə-vī′rĭn)n.
A synthetic antiviral ribonucleoside that inhibits DNA and RNA replication, used to treat lung infections caused by respiratory syncytial virus in infants and young children and in combination with an interferon to treat hepatitis C infection.
[Probably RIB(ONUCLEIC) A(CID) + VIR(US) + -IN.]