Moldy or musty.
Stale-smelling or stuffy.
(figuratively, by extension) old-fashioned, refusing to change or update.
(of wine) Tasting of the cask.
(obsolete) To decay.
* 1602 : , act IV scene 4
- Sure he that made us with such large discourse
- Looking before and after, gave us not
- That capability and godlike reason
- To fust in us unused.
A strong musty smell; mustiness.