Storey or level (5)
I believe the answer is:
floor
I believe this is a double definition.
'storey' is the first definition.
(I know that storey can be written as floor)
'level' is the second definition.
(I know that level can be written as floor)
(Other definitions for floor that I've seen before include "Part of building" , "Knock down with force" , "Fox" , "Minimum (price) level" , "American's story" .)