Misplaced trust in a nudist (8)
I believe the answer is:
naturist
'nudist' is the definition.
(synonyms)
'misplaced trust in a' is the wordplay.
'misplaced' indicates anagramming the letters (letters in the wrong places).
'trust'+'in'+'a'='trustina'
'trustina' is an anagram of 'NATURIST'.
(Other definitions for naturist that I've seen before include "One who believes in going nude" , "One who wears nothing out" , "one barely feeling comfortable" , "One exposed" , "Another word for nudist" .)