Social worker's right to tackle fierce puzzle (8)
I believe the answer is:
bewilder
'puzzle' is the definition.
(synonyms)
'social worker's right to tackle fierce' is the wordplay.
'social worker' becomes 'bee'.
'right' becomes 'r' (common abbreviation).
'to tackle' means one lot of letters goes inside another (tackle can mean to take hold of).
'fierce' becomes 'wild' (similar in meaning).
'bee'+'r'='beer'
'beer' enclosing 'wild' is 'BEWILDER'.
(Other definitions for bewilder that I've seen before include "Confuse totally" , "Deli brew (anag.)" , "Confuse utterly" , "fox" , "Confuse, puzzle" .)