Criticise great answer that makes everything better (7)
I believe the answer is:
panacea
'makes everything better' is the definition.
I can't judge whether this defines the answer.
'criticise great answer' is the wordplay.
'criticise' becomes 'pan' (informal term meaning to criticise heavily).
'great' becomes 'ace' (ace can informally mean very good).
'answer' becomes 'a' (abbreviation eg in Q and A).
'pan'+'ace'+'a'='PANACEA'
'that' acts as a link.
Can you help me to learn more?
(Other definitions for panacea that I've seen before include "Remedy for all kinds of diseases or troubles" , "Cure for all ills" , "sovereign remedy" , "A cure for everything" , "comprehensive fix" .)