flysheet
Definitions
A waterproof cover placed over a tent to provide extra protection from rain and wind.
A single sheet of paper or a leaflet, often used for advertising or information distribution.
A protective outer layer or flap on a garment, such as the covering over a zipper.
Examples
We attached the waterproof flysheet to the tent to protect us from the unexpected rainstorm.
Make sure the flysheet is pulled taut so that condensation does not build up inside the tent overnight.