The Collaborative International Dictionary of English v.0.48:
Level \Lev"el\ (l[e^]v"[e^]l), a.
1. Even; flat; having no part higher than another; having, or
conforming to, the curvature which belongs to the
undisturbed liquid parts of the earth's surface; as, a
level field; level ground; the level surface of a pond or
Ample spaces o'er the smooth
And level pavement. --Milton.
2. Coinciding or parallel with the plane of the horizon;
horizontal; as, the telescope is now level.
3. Even with anything else; of the same height; on the same
line or plane; on the same footing; of equal importance;
-- followed by with, sometimes by to.
Young boys and girls
Are level now with men; the odds is gone. --Shak.
Everything lies level to our wish. --Shak.
4. Straightforward; direct; clear; open.
A very plain and level account. --M. Arnold.
5. Well balanced; even; just; steady; impartial; as, a level
head; a level understanding. [Colloq.] " A level
6. (Phonetics) Of even tone; without rising or falling
inflection. --H. Sweet.
Level line (Shipbuilding), the outline of a section which
is horizontal crosswise, and parallel with the rabbet of
the keel lengthwise.
Level surface (Physics), an equipotential surface at right
angles at every point to the lines of force.