level
/ˈle-vəl/
noun
a device for establishing a horizontal line or plane by means of a bubble in a liquid that shows adjustment to the horizontal by movement to the center of a slightly bowed glass tube
a measurement of the difference of altitude of two points by means of a level
horizontal condition; especially : equilibrium of a fluid marked by a horizontal surface of even altitude
verb
to make (a line or surface) horizontal : make flat or level
to bring to a horizontal aiming position
aim, direct
level a field
adjective
having no part higher than another : conforming to the curvature of the liquid parts of the earth's surface
parallel with the plane of the horizon : horizontal
even or unvarying in height