- principal plane of symmetry
**:**a plane of symmetry in a crystal that includes two or more axes of symmetry

*Useful english dictionary.
2012.*

- principal plane of symmetry
**:**a plane of symmetry in a crystal that includes two or more axes of symmetry

*Useful english dictionary.
2012.*

**principal axis**— i. The lateral, vertical, and longitudinal axes. ii. The axis of relative wind. iii. The principal inertial axis: that line passing through the center of gravity in a plane of symmetry about which a long, slender body tends to rotate when rolling … Aviation dictionary**Symmetry operation**— In the context of molecular symmetry, a symmetry operation may be defined as a permutation of atoms such that the molecule or crystal is transformed into a state indistinguishable from the starting state. Two basic facts follow from this… … Wikipedia**principal axis**— Axis Ax is, n.; pl. {Axes}. [L. axis axis, axle. See {Axle}.] A straight line, real or imaginary, passing through a body, on which it revolves, or may be supposed to revolve; a line passing through a body or system around which the parts are… … The Collaborative International Dictionary of English**Molecular symmetry**— in chemistry describes the symmetry present in molecules and the classification of molecules according to their symmetry. Molecular symmetry is a fundamental concept in chemistry, as it can predict or explain many of a molecule s chemical… … Wikipedia**Axis of symmetry**— Axis Ax is, n.; pl. {Axes}. [L. axis axis, axle. See {Axle}.] A straight line, real or imaginary, passing through a body, on which it revolves, or may be supposed to revolve; a line passing through a body or system around which the parts are… … The Collaborative International Dictionary of English**Axes of coordinates in a plane**— Axis Ax is, n.; pl. {Axes}. [L. axis axis, axle. See {Axle}.] A straight line, real or imaginary, passing through a body, on which it revolves, or may be supposed to revolve; a line passing through a body or system around which the parts are… … The Collaborative International Dictionary of English**Cardinal point (optics)**— For other uses, see Cardinal point (disambiguation). In Gaussian optics, the cardinal points consist of three pairs of points located on the optical axis of an ideal, rotationally symmetric, focal, optical system. For ideal systems, the basic… … Wikipedia**Differential geometry of surfaces**— Carl Friedrich Gauss in 1828 In mathematics, the differential geometry of surfaces deals with smooth surfaces with various additional structures, most often, a Riemannian metric. Surfaces have been extensively studied from various perspectives:… … Wikipedia**X-ray crystallography**— can locate every atom in a zeolite, an aluminosilicate with many important applications, such as water purification. X ray crystallography is a method of determining the arrangement of atoms within a crystal, in which a beam of X rays strikes a… … Wikipedia**Rigid body**— Classical mechanics Newton s Second Law History of classical mechanics … Wikipedia