Decks (6)
I believe the answer is:
floors
'decks' is the definition.
(I know this)
This is all the clue.
(Other definitions for floors that I've seen before include "Knocks person down in a fight or confounds" , "Tiers in a building" , "Baffles completely" , "Stumps (with question)" , "Knocks down with a punch" .)