Wiktionary
guyline
alt. A rope or cable (a line) used to restrain the motion of something. As a cable used to prevent a mast from falling over. n. A rope or cable (a line) used to restrain the motion of something. As a cable used to prevent a mast from falling over.
Usage examples of "guyline".
The balance mast actually was mostly hidden in the clouds below and I was able to grab a guyline and swing over to it just as I passed into the mist.
Vascay stepped on a corner of the canvas, pinning it to the ground, and instead tossed Garric a tunic draped over a guyline anchoring an overhead tarp.