in geometry, the lowest side of the perimeter of a figure: Thus, the base of a triangle may be said of any of its sides, but more properly of the lowest, or that which is parallel to the horizon. In rectangles triangles, the base is properly that side opposite to the right angle.

Base of a Solid Figure, the lowest side, or that on which it stands.

Base of a Conic Section, a right line in the hyperbola and parabola, arising from the common intersection of the secant plain and the base of the cone.

Base, in architecture, is used for any body which bears another, but particularly for the lower part of a column and pedestal.—The ancients, in the early times of architecture, used no bases. The Doric columns in the temple of Minerva at Athens have none, but stand immediately upon the floor of the porch. Columns afterwards came to be supported on square pieces called plinths, and after that on pedestals. When we see a column, of whatsoever order, on a pedestal, the base is that part which comes between the top of the pedestal and the bottom of the shaft of the column; when there is no pedestal, it is the part between the bottom of the column and the plinth: some have included the plinth as a part of the base; but it is properly the piece on which the base stands, as the column stands upon that.—The pedestal also has its base as well as the column, and the pilaster. The base of columns is differently formed in the different orders; but in general it is composed of certain spires or circles, and was thence in early times called the spire of a column. These circles were in this case supposed to represent the folds of a snake as it lies rolled up; but they are properly the representations of several larger and smaller rings or circles of iron, with which the trunk of trees which were the ancient columns were surrounded to prevent their bursting: these were rude and irregular, but the sculptor who imitated them in stone found the way to make them elegant.

Base, in fortification, the exterior side of the polygon, or that imaginary line which is drawn from the flanked angle of a bastion to the angle opposite to it.

Base, in gunnery, the least fort of ordnance, the diameter of whose bore is 1½ inch, weight 200 pound, length 4 feet, load 5 pound, shot 1½ pound weight, and diameter 1½ inch.

Base, in chemistry. See Basis.

Base, in law. Base estate, such as base tenants have in their hands. Base tenure, the holding by villainage, or other customary services; as distinguished from the higher tenures in capite, or by military service. Base fee, is to hold in fee at the will of the lord, as distinguished from foggage tenure. Base court, any court not of record.