Bewildered prisoner mingled (8)
I believe the answer is:
confused
'bewildered' is the definition.
(synonyms)
'prisoner mingled' is the wordplay.
'prisoner' becomes 'con' (abbreviation for 'convict').
'mingled' becomes 'fused' (both can mean joined together).
'con'+'fused'='CONFUSED'
(Other definitions for confused that I've seen before include "at sea" , "Haywire" , "Unable to think clearly, bewildered" , "Bewildered, perplexed" , "Perplexed, befuddled" .)