Prisoner - cite stranger with complacency (7)
I believe the answer is:
conceit
'complacency' is the definition.
(thesaurus)
'prisoner cite stranger' is the wordplay.
'prisoner' becomes 'con' (abbreviation for 'convict').
'stranger' is an anagram indicator.
'cite' with letters rearranged gives 'ceit'.
'con'+'ceit'='CONCEIT'
'with' acts as a link.
(Other definitions for conceit that I've seen before include "Fanciful notion; excessive pride in oneself" , "Overbearing self-esteem" , "Self-importance - idea" , "Fancy; vanity" , "Excessive self-pride" .)