Use needles and wool (4)
I believe the answer is:
knit
'use needles and wool' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for knit that I've seen before include "Use needles to make clothes" , "Bind together" , "Arrears" , "(Bone) heal; contract (brows)" , "Join together (with needles)" .)