Meat accompanies fibre in hamper (9)
I believe the answer is:
hamstring
'hamper' is the definition.
(I've seen this before)
'meat accompanies fibre' is the wordplay.
'meat' becomes 'ham' (ham is a kind of meat).
'accompanies fibre' becomes 'string' (I can't justify this - if you can you should give a lot more credence to this answer).
'ham'+'string'='HAMSTRING'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for hamstring that I've seen before include "hamper" , "Thwart, severely restrict" , "Tendon behind the knee" , "Impede" , "Cramp the style of" .)