Mŭst'y, a.

a. [compar. MUSTIER; superl. MUSTIEST.]

1. Moldy; sour; foul and fetid; as, a musty cask; musty corn or straw; musty books.
2. Spoiled by age; stale.

The proverb is somewhat musty. Shak. 3. Dull; heavy; spiritless. “That he may not grow musty and unfit for conversation.” Addison.