mycophenolic acid /ˌmaɪ.koʊ.fɪˌnoʊ.lɪk ˈæs.ɪd/ noun1 •A crystalline antibiotic C₁₇H₂₀O₆ obtained from fungi of the genus Penicillium, used as an immunosuppressant drug to prevent rejection in organ transplants. formsmycophenolic acids