Used a neat manoeuvre when sickened (9)
I believe the answer is:
nauseated
'sickened' is the definition.
('nauseate' can be a synonym of 'sicken')
'used a neat manoeuvre' is the wordplay.
'manoeuvre' indicates anagramming the letters.
'used'+'a'+'neat'='usedaneat'
'usedaneat' anagrammed gives 'NAUSEATED'.
'when' acts as a link.
(Other definitions for nauseated that I've seen before include "Revolted" , "Disgusted" , "Sickened" .)