Indifferent support restricting Liberal (5)
I believe the answer is:
blase
'indifferent' is the definition.
(I've seen this in another clue)
'support restricting liberal' is the wordplay.
'support' becomes 'base' (base is a kind of support).
'restricting' means one lot of letters goes inside another.
'liberal' becomes 'l' (abbreviation).
'base' going around 'l' is 'BLASE'.
(Other definitions for blase that I've seen before include "Having a "seen it all before" attitude" , "Bored with sable" , "Unimpressed, offhand" , "Nonchalantly unconcerned" , "Surfeited with pleasure" .)