bare, cold, hard
I can't sleep on the bare floor!

dirty, dusty
wet
clean, polished, smooth
cement, concrete, stone
dirt (esp. AmE)
hardwood, parquet, wood, wooden
carpeted, linoleum, marble, tiled
bathroom, kitchen, etc.
raised
dance

clean, mop, polish, scrub, sweep, wash, wax, wipe
drop to, fall to
His glass fell to the floor and broke.

hit
reach, touch
pace, walk
cover, litter

covering, mat, tile
lamp (esp. AmE)
space
exercises
plan

on the floor
Do you mind sitting on the floor?

from floor to ceiling
Bookcases lined the walls from floor to ceiling.

canyon, cave, desert, forest, ocean, sea, valley

bottom, first (= at entrance level), ground (BrE)
top
first, second, third, etc. (In BrE, the first floor is the floor above the entrance level. This is called the second floor in AmE.)
mezzanine
lower, upper

occupy
The offices occupy the top floor of the building.

on the floor
a cafe on the mezzanine floor