The Collaborative International Dictionary of English v.0.48:
Square \Square\ (skw[^a]r), a.
1. (Geom.) Having four equal sides and four right angles; as,
a square figure.
2. Forming a right angle; as, a square corner.
3. Having a shape broad for the height, with rectilineal and
angular rather than curving outlines; as, a man of a
4. Exactly suitable or correspondent; true; just.
She's a most triumphant lady, if report be square to
5. Rendering equal justice; exact; fair; honest; as, square
6. Even; leaving no balance; as, to make or leave the
7. Leaving nothing; hearty; vigorous.
By Heaven, square eaters.
More meat, I say. --Beau. & Fl.
8. (Naut.) At right angles with the mast or the keel, and
parallel to the horizon; -- said of the yards of a
square-rigged vessel when they are so braced.
Note: Square is often used in self-explaining compounds or
combinations, as in square-built, square-cornered,
square-cut, square-nosed, etc.
Square foot, an area equal to that of a square the sides of
which are twelve inches; 144 square inches.
Square knot, a knot in which the terminal and standing
parts are parallel to each other; a reef knot. See Illust.
Square measure, the measure of a superficies or surface
which depends on the length and breadth taken conjointly.
The units of square measure are squares whose sides are
the linear measures; as, square inches, square feet,
square meters, etc.
Square number. See Square, n., 6.
Square root of a number or Square root of a quantity
(Math.), that number or quantity which, multiplied by
itself, produces the given number or quantity.
Square sail (Naut.), a four-sided sail extended upon a yard
suspended by the middle; sometimes, the foresail of a
schooner set upon a yard; also, a cutter's or sloop's sail
boomed out. See Illust. of Sail.
Square stern (Naut.), a stern having a transom and joining
the counter timbers at an angle, as distinguished from a
round stern, which has no transom.
Three-square, Five-square, etc., having three, five,
etc., equal sides; as, a three-square file.
To get square with, to get even with; to pay off. [Colloq.]