### Clue: US independent study with arbitrator (7)
### Answer: MUGWUMP 
 ### Explanation: Definition: US independent
 MUG(to study as far as possible in a short time) + W(abbrev. for "with") + UMP(short for "umpire"/arbitrator in a match, say).
Defn: In the US, one who remains independent/does not participate in party politics.