Rejected matter not available to a Liberal (5)
I believe the answer is:
offal
'rejected matter' is the definition.
'offal' can be an answer for 'matter' (offal is a kind of matter). I'm unsure of the 'rejected' bit.
'not available to a liberal' is the wordplay.
'not available' becomes 'off' (I've seen this in other clues).
'to a liberal' becomes 'al' (I've seen this in other clues).
'off'+'al'='OFFAL'
Can you help me to learn more?
(Other definitions for offal that I've seen before include "Animal entrails and internal organs as rubbish" , "Entrails used as food" , "cheap meat" , "Internal organs of an animal used as food" , "Heart, liver, kidney etc" .)