Who’ll eat these slops? (8)
I believe the answer is:
pigswill
'who'll' is the definition.
Both the definition and answer are singular nouns.
Perhaps there's an association between them I don't understand?
'eat these slops?' is the wordplay.
'eat' becomes 'pig' (pigging is a kind of eating).
'these slops?' becomes 'swill' ('swill' can be a synonym of 'slops'**).
'pig'+'swill'='PIGSWILL'
(Other definitions for pigswill that I've seen before include "Refuse" , "kitchen waste" , "Leftover food for the sty" , "waste matter?" , "Scraps for swine" .)