Social worker one political opponent (4)
I believe the answer is:
anti
'political opponent' is the definition.
'anti' can be an answer for 'opponent' (someone opposed to something). I am not certain of the 'political' bit.
'social worker one' is the wordplay.
'social worker' becomes 'ant' (ants are social insects).
'one' becomes 'i' (Roman numeral).
'ant'+'i'='ANTI'
Can you help me to learn more?
(Other definitions for anti that I've seen before include "Prefix meaniing against" , "Against, informally" , "Prefix meaning against" , "An opponent - opposed to party policy, etc" , "one opposing?" .)