Agile circus performer (7)
I believe the answer is:
acrobat
'agile circus performer' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for acrobat that I've seen before include "Agile circus performer" , "Taco bar (anag.)" , "Circus star" , "Tumbler" , "Tightrope-walker" .)