2. A land area of uniform elevation: "The pictures were hung on the wall at eye level."
3. Etymology: The Latin word for a "balance" or "scales" was libra. English took it as The zodiacal sign and it lies behind many terms for units of measurement, including litre, or liter and the abbreviation lb or £ for British currency known as the "pound".
Its diminutive form was libella, which denoted an "instrument for checking horizontally" and hence a "horizontal line".
It passed into Old French as livel; which in modern French has become niveau, "level", and it entered English as level.
2. To render people or things equal; to equalize: "The mayor wants to level the opportunities for smaller companies to compete against the big companies in the city."
3. To direct something against a person or group: "Several complaints have been leveled against the government for not responding to the economic crisis that is causing so many people to lose their jobs."
4. To speak honestly to someone: "Rebecca's co-worker never leveled with her about backing his car into her vehicle in the parking lot."
"The recipe indicated that there should be a level tablespoon of sugar which fills the spoon exactly without going any higher than the edges."
2. Descriptive of being without irregularities, roughness, or indentations: "The carpenter made the floor as smooth and level as possible."
3. Steady and calm: "The teacher spoke to her students in a level voice when she told them that everyone had passed the test."
"Brian's brother tried his level best to win the race."
2. A part of a building which is at a specified height: Reservations were made so Nathan and Josie could have good seats in the upper level of the theater.
3. A process of thinking about, talking about, or dealing with something: Philip thought that the politician's position was acceptable on an emotional level, but not on a practical level.
Dale, will you level with me? Are the pictures hanging on the right level?

2. A quantum-mechanical concept for energy levels of electrons around the nucleus.
Electron energies are functions of each particular atomic species.
The vials are filled with liquid, and an air bubble is left to aid in the determination of the horizontal plane and highest vertical point.
The higher the power output, the longer the read range, but most governments regulate power levels to avoid interference with other devices.
In a metal, the Fermi level is very near the top of the filled levels in the partially filled valence band. In a semiconductor, the Fermi level is in the band gap.