Bitter, getting caught in hunt (5)
I believe the answer is:
scour
'hunt' is the definition.
(thesaurus)
'bitter getting caught' is the wordplay.
'bitter' becomes 'sour' (I've seen this in another clue).
'getting' means one lot of letters goes inside another.
'caught' becomes 'c' (cricket abbreviation).
'sour' placed around 'c' is 'SCOUR'.
'in' acts as a link.
(Other definitions for scour that I've seen before include "Clean by abrasion" , "Thoroughly clean" , "Clean by hard rubbing" , "search in detail" , "Rub hard or search thoroughly" .)