The caliber of empty tubes. --Reid.
A battery composed of three guns of small caliber.
--Prescott.
Note: The caliber of firearms is expressed in various ways.
Cannon are often designated by the weight of a solid
spherical shot that will fit the bore; as, a
12-pounder; pieces of ordnance that project shell or
hollow shot are designated by the diameter of their
bore; as, a 12 inch mortar or a 14 inch shell gun;
small arms are designated by hundredths of an inch
expressed decimally; as, a rifle of .44 inch caliber.
2. The diameter of round or cylindrical body, as of a bullet
or column.
3. Fig.: Capacity or compass of mind. --Burke.
{Caliber compasses}. See {Calipers}.
{Caliber rule}, a gunner's calipers, an instrument having two
scales arranged to determine a ball's weight from its
diameter, and conversely.
{A ship's caliber}, the weight of her armament.