Disconcerted to be knocked down (7)
I believe the answer is:
floored
'be knocked down' is the definition.
(I've seen this in another clue)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for floored that I've seen before include "Threw" , "Completely baffled" , "Knocked out" , "Completely confounded" , "stumped" .)