Knitter's need (4)
I believe the answer is:
wool
'knitter's need' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for wool that I've seen before include "Sheep's fleece" , "Where the Lord Chancellor sits" , "Fabric from fleece" , "Fleece of sheep" , "It could become felt" .)