After revolution liberators lost IRA support (7)
I believe the answer is:
bolster
'support' is the definition.
(synonyms)
'after revolution liberators lost ira' is the wordplay.
I cannot really understand how this works, but
an anagram of 'lost' is 'olst' which is present in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for bolster that I've seen before include "Prop up with long pillow" , "Provide reinforcement" , "Extended pillow" , "Reinforce; a cushion" , "Support; long pillow" .)