This taper worried analyst (9)
I believe the answer is:
therapist
'analyst' is the definition.
(thesaurus)
'this taper worried' is the wordplay.
'worried' indicates anagramming the letters.
'this'+'taper'='thistaper'
'thistaper' is an anagram of 'THERAPIST'.
(Other definitions for therapist that I've seen before include "Help" , "nurse" , "Provider of relieving 57 Across" , "healing type" , "Shrink" .)