lev·el 
(lĕvəl)
(lĕvəl)n.
1.
a. Relative position or rank on a scale: the local level of government; studying at the graduate level.
b. A relative degree, as of achievement, intensity, or concentration: an unsafe level of toxicity; a high level of frustration.
2. A natural or proper position, place, or stage: I finally found my own level in the business world.
3. Position along a vertical axis; height or depth: a platform at knee level.
4.
a. A horizontal line or plane at right angles to the plumb.
b. The position or height of such a line or plane.
5. A flat, horizontal surface.
6. A land area of uniform elevation.
7.
a. An instrument for ascertaining whether a surface is horizontal, vertical, or at a 45° angle, consisting essentially of an encased, liquid-filled tube containing an air bubble that moves to a center window when the instrument is set on an even plane. Also called spirit level.
b. Such a device combined with a telescope and used in surveying.
c. A computation of the difference in elevation between two points by using such a device.
adj.
1. Having a flat, smooth surface: a level countertop.
2. Being on a horizontal plane: a level field.
3.
a. Being at the same height or position as another; even.
b. Being at the same degree of rank, standing, or advantage as another; equal.
c. Being or relating to a specified rank or standing. Often used in combination: a lower-level administrator.
4. Exhibiting no abrupt variations; steady: spoke in a level tone.
5. Rational and balanced; sensible: came to a level appraisal of the situation; keeps a level head in an emergency.
6. Filled evenly to the top: a level tablespoon of the medicine.
v. lev·eled, lev·el·ing, lev·els or lev·elled or lev·el·ling
v.tr.
1.
a. To make horizontal, flat, or even: leveled the driveway with a roller; leveled off the hedges with the clippers.
b. To place on the same rank; equalize.
2.
a. To tear down (a building, for example); raze.
b. To knock down, as with a blow; lay low: leveled the opponent with an uppercut.
3.
a. To aim along a horizontal plane: leveled the gun at the target.
b. To direct emphatically or forcefully toward someone: leveled charges of dishonesty. See Synonyms at aim.
4. To measure the different elevations of (a tract of land) with a level.
v.intr.
1. To bring persons or things to an equal level; equalize.
2. To aim a weapon horizontally.
3. Informal To be frank and open: advised the suspect to level with the authorities.
adv.
Phrasal Verb: Along a flat or even line or plane.
level off
Idioms: 1. To move toward stability or consistency: Prices leveled off.
2. To maneuver an aircraft into a flight attitude that is parallel to the surface of the earth after gaining or losing altitude.
(one's) level best
The best one can do in an earnest attempt: I did my level best in math class.
on the level Informal
Without deception; honest.
[Middle English, an instrument to check that a surface is horizontal, from Old French livel, from Vulgar Latin *lībellum, from Latin lībella, diminutive of lībra, balance.]
level·ly adv.
level·ness n.
Synonyms: level, flat1, even1, plane1, smooth, flush1
These adjectives describe surfaces without elevations or depressions. Level implies being parallel with the line of the horizon: acres of level farmland. Flat applies to surfaces without curves, protuberances, or indentations: "There were no woods behind the yard, just an expanse of flat cleared land and then a hill that sloped down into the former quarry" (Frederick Reiken).
Even refers to flat surfaces in which no part is higher or lower than another: the even surface of the mirror. Plane is a mathematical term referring to a surface containing all the straight lines connecting any two points on it: a plane figure. Smooth describes a surface on which the absence of irregularities can be established by sight or touch: smooth marble. Flush applies to a surface that is on an exact level with an adjoining one: The door is flush with the wall. See Also Synonyms at aim.
These adjectives describe surfaces without elevations or depressions. Level implies being parallel with the line of the horizon: acres of level farmland. Flat applies to surfaces without curves, protuberances, or indentations: "There were no woods behind the yard, just an expanse of flat cleared land and then a hill that sloped down into the former quarry" (Frederick Reiken).
Even refers to flat surfaces in which no part is higher or lower than another: the even surface of the mirror. Plane is a mathematical term referring to a surface containing all the straight lines connecting any two points on it: a plane figure. Smooth describes a surface on which the absence of irregularities can be established by sight or touch: smooth marble. Flush applies to a surface that is on an exact level with an adjoining one: The door is flush with the wall. See Also Synonyms at aim.