diameter

n. [ F. diamètre, L. diametros, fr. Gr. &unr_;; dia` through + &unr_; measure. See Meter. ] 1. (Geom.) (a) Any right line passing through the center of a figure or body, as a circle, conic section, sphere, cube, etc., and terminated by the opposite boundaries; a straight line which bisects a system of parallel chords drawn in a curve. (b) A diametral plane. [ 1913 Webster ]

2. The length of a straight line through the center of an object from side to side; width; thickness; as, the diameter of a tree or rock. [ 1913 Webster ]

☞ In an elongated object the diameter is usually taken at right angles to the longer axis. [ 1913 Webster ]

3. (Arch.) The distance through the lower part of the shaft of a column, used as a standard measure for all parts of the order. See Module. [ 1913 Webster ]

Conjugate diameters. See under Conjugate. [ 1913 Webster ]