- For the backstay of a boot (footwear), see Boot#Parts of a boot.
A
backstay is a piece of
standing rigging on a
sailing vessel that runs from the
mast to either its
transom or rear quarter, counteracting the
forestay and
jib. It is an important sail trim control and has a direct effect on the shape of the
mainsail and the
headsail. Backstays are generally adjusted by
block and tackle,
hydraulic adjusters, or lines leading to winches.