Mus"ty (?), a. [Compar. Mustier (?); superl. Mustiest.] [From L. mustum must; or perh. fr. E. moist. Cf. Must, n., Moist.]
1.
Having the rank, pungent, offencive odor and taste which substances of organic origin acquire during warm, moist weather; foul or sour and fetid; moldy; as, musty corn; musty books.
Harvey.
2.
Spoiled by age; rank; stale.
The proverb is somewhat musty.
Shak.
3.
Dull; heavy; spiritless.
"That he may not grow
musty and unfit for conversation."
Addison.
© Webster 1913.