### Clue: Note sharp double bends laid with a square floor (9)
### Answer: MEZZANINE 
 ### Explanation: Definition: floor
 ME(or "mi", the third note of a major musical scale) + ZZ(letters representing two double bends, each shaped like a "Z" – bends in a road, say) **plus**(laid with) A + NINE(the square of the number 3).
Defn: A floor between two others in a building.