Lewis Short
(adjective) : mustĕus, a, um, mustum
* Of or belonging to new wine or must, like must.
* Lit.: mala, quae antea mustea vocabant, nunc melimela appellant,must-apples,Cato, R. R. 7, 3: mala,Plin. 15, 14, 15, § 51: fructus,Col. 9, 15, 13.
* Transf., young, new, fresh (post-Aug.): musteus caseus,Plin. 11, 42, 97, § 240: piper,id. 12, 7, 14, § 29: liber,Plin. Ep. 8, 21, 6.
Charlton T. Lewis, Charles Short, A Latin Dictionary