I. ˈ ̷ ̷ˌ ̷ ̷ noun
Etymology: back (III) + stay
1.
a. : a stay extending from the mastheads to the side of a ship and slanting a little aft — see ship illustration
b. : a supporting cable (as on a derrick) that prevents a falling forward of a more or less vertical part
2. : any of various strengthening or supporting devices at the back or rear:as
a. : a rope or strap to prevent excessive forward motion (as of the carriage in a hand printing press)
b. : a spring used to keep the cutting edges of purchase shears in contact
c. : a bar topped with a glass rod running across a loom below the lowest motion of the warp yarns
d. : a rod extending from either end of the rear axle of a carriage to the reach
e. : a strip of leather covering and strengthening the back seam of a shoe
II. transitive verb
: to rig with backstays