### Clue: Naval officer captures British force? Excellent! (9)
### Answer: ADMIRABLE 
 ### Explanation: Definition: Excellent
 [ ADMIRAL(a senior naval officer) **containing**(captures) B(abbrev. for "British") ] + E(symbol for "electromotive force" in physics, though a preferable symbol would be "emf", to distinguish it from "energy", the quantity more familiarly symbolised by "E" ].