# The correct espression for something’s surface is parallel to the ground level?

Like the title says, I thought it was something like “the kitchen table is now level” but I’m not sure anymore.

• "Level" means the surface is everywhere perpendicular to the plane defined by the line of a "plumb-bob" (a plumb-line). A snowboard going down the mountainside is not level, even though it's parallel to the ground.
– TimR
Commented Nov 18, 2014 at 20:59
• Do you mean parallel with the ground or so that something round won't roll off it? If you put a table on the side of a hill, would you want it parallel with the sloping ground or with the horizon? ("Horizontal" has already been suggested at the time of commenting.) Commented Nov 19, 2014 at 4:53
• TRomano got it right- "level" is perpendicular to the geiod, i.e. the mathematical surface of the Earth which is perpendicular to the force of gravity. Plumb bobs are always parallel to the force of gravity at that location, so anything perpendicular to them is level. "Ground level" has nothing to do with it. Commented Nov 19, 2014 at 8:01