catch-cord

[ kach-kawrd ]
/ ˈkætʃˌkɔrd /

noun Textiles.

a cord or wire located near a selvage, used to form a loop or deflect the filling yarn not intended to be woven permanently in with the regular selvage.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019