Check by placing the level across one of the cabinet's horizontal surfaces.
The side panel folds down to become a horizontal surface for writing and working.
A floor is a horizontal surface inside a building.
Every horizontal surface was covered with a layer of dust.
Cut the pieces so that they fit against the step and their top edges are even with the step's horizontal surface.
They will then hang upside down on a horizontal surface.
Pitch is changed in this case by moving the entire horizontal surface of the tail.
It was clean, for one thing, with polish gleaming on every horizontal surface.
Almost every other horizontal surface in the room was equally cluttered.
The only way these two objects would line up was if the instrument rested on a horizontal surface.
