Rapid bustling commotion (3)
I believe the answer is:
ado
'rapid bustling commotion' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for ado that I've seen before include "carry-on" , "Fuss, difficulty" , "puff ball!" , "Shakespeare: 'Much ... About Nothing'(3) ()" , "Song and dance" .)