1. having a stale, musty, or stuffy smell or atmosphere
Usage: superlative form of frowsy

Examples

• The basement was the frowsiest room in the old house.
• After being closed up all winter, the cabin had the frowsiest air imaginable.
• She opened all the windows to air out the frowsiest corners of the attic.
• The frowsiest part of the library was the rarely used storage room.
• Even after cleaning, that was still the frowsiest closet in the building.