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—axised /ak"sist/, adj.1. the line about which a rotating body, such as the earth, turns.2. Math.a. a central line that bisects a two-dimensional body or figure.b. a line about which a three-dimensional body or figure is symmetrical.3. Anat.a. a central or principal structure, about which something turns or is arranged: the skeletal axis.b. the second cervical vertebra.4. Bot. the longitudinal support on which organs or parts are arranged; the stem and root; the central line of any body.5. Analytic Geom. any line used as a fixed reference in conjunction with one or more other references for determining the position of a point or of a series of points forming a curve or a surface. Cf. x-axis, y-axis.7. Aeron. any one of three lines defining the attitude of an airplane, one being generally determined by the direction of forward motion and the other two at right angles to it and to each other.8. Fine Arts. an imaginary line, in a given formal structure, about which a form, area, or plane is organized.9. an alliance of two or more nations to coordinate their foreign and military policies, and to draw in with them a group of dependent or supporting powers.10. the Axis, (in World War II) Germany, Italy, and Japan, often with Bulgaria, Hungary, and Rumania.11. a principal line of development, movement, direction, etc.[1540-50; < L axis an axletree, axle, axis. See AXI-]axis2/ak"sis/, n., pl. axises.See axis deer.
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▪ crystalsin crystallography, any of a set of lines used to describe the orderly arrangement of atoms in a crystal. If each atom or group of atoms is represented by a dot, or lattice point, and these points are connected, the resulting lattice may be divided into a number of identical blocks, or unit cells. The intersecting edges of one of these unit cells are chosen as the crystallographic axes, and their lengths are called lattice constants. The relative lengths of these edges and the angles between them place the solid into one of the seven crystal systems. (See crystal (silica mineral).) The position of an atom within a unit cell is given in terms of the crystallographic axes, and planes in the crystal are described using the axes.* * *
Universalium. 2010.