floor

The interior bottom or surface of a house or building; the supporting surface of a room.

"The room has a wooden floor."

Ground (surface of the Earth, as opposed to the sky or water or underground).

The lower inside surface of a hollow space.

"Many sunken ships rest on the ocean floor."

To cover or furnish with a floor.

"floor a house with pine boards"

To strike down or lay level with the floor; to knock down.

(driving) To accelerate rapidly.

"As soon as our driver saw an insurgent in a car holding a detonation device, he floored the pedal and was 2,000 feet away when that car bomb exploded. We escaped certain death in the nick of time!"