Dead set about being relaxed (7)
I believe the answer is:
sedated
'relaxed' is the definition.
Both the definition and answer are adjectives. Maybe you can see an association between them that I don't see?
'dead set about' is the wordplay.
'about' indicates anagramming the letters.
'dead'+'set'='deadset'
'deadset' with letters rearranged gives 'SEDATED'.
'being' is the link.
Can you help me to learn more?
(Other definitions for sedated that I've seen before include "Under the influence of drugs" , "Tranquillized" , "Dead set (anag) - tranquillised" , "Calmed with drugs" , "Given a tranquilliser" .)