Most worthless parts (5)
I believe the answer is:
dregs
'most worthless parts' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for dregs that I've seen before include "Wine or coffee residue" , "Sediment - rabble" , "Sediment at bottom of drink" , "Bottom of the barrel" , "Liquid remnants with sediment" .)