Thick string (4)
(Other definitions for twine that I've seen before include "Thin cord" , "can get into knots" , "Twisted cord" , "Interweave" , "Curl; string" .)
'thick string' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for cord that I've seen before include "Thin string" , "Rope; fabric" , "Small rope; flex" , "Small rope or thick string" , "Line of twisted fibres or threads" .)