Tumbler -- a member of the rook family? Not quite: another flying creature (7)
I believe the answer is:
acrobat
'tumbler' is the definition.
(synonyms)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for acrobat that I've seen before include "Agile entertainer" , "Boat car (anag.)" , "Performing gymnast" , "Taco bar (anag.)" , "performer of risky feats?" .)