Taken to be fitting in better? (8)
I believe the answer is:
captured
'taken' is the definition.
(capturing is a kind of taking)
'fitting in better?' is the wordplay.
'fitting' becomes 'apt' (both mean appropriate).
'in' indicates putting letters inside.
'better?' becomes 'cured' (after being sick).
'apt' placed inside 'cured' is 'CAPTURED'.
'to be' acts as a link.
(Other definitions for captured that I've seen before include "Prisoners" , "Apprehended" , "Arrested, seized" , "Took prisoner" , "Caught, seized after a chase" .)