Retaliation from salesperson beside Republican with one girl (8)
I believe the answer is:
reprisal
'retaliation from salesperson' is the definition.
'reprisal' can be an answer for 'retaliation' (reprisal is a kind of retaliation). I am not sure about the 'from salesperson' bit.
'beside republican with one girl' is the wordplay.
'beside' means one lot of letters go next to another.
'republican' becomes 'rep'.
'with one' becomes 'ri' (I can't explain this - if you can you should give a lot more credence to this answer).
'girl' becomes 'Sal' (feminine given name).
'rep' put next to 'ri' is 'repri'.
'repri'+'sal'='REPRISAL'
Can you help me to learn more?
(Other definitions for reprisal that I've seen before include "Retaliatory action against an enemy" , "hitting back" , "Act of retaliation or vengeance" , "Counterattack" , "Retaliation for an injury" .)