principal axis


noun
  1. Optics. a line passing through the center of the surface of a lens or spherical mirror and through the centers of curvature of all segments of the lens or mirror.

  2. Physics. one of three mutually perpendicular axes of a body about which the moment of inertia is maximum or minimum.

Origin of principal axis

1
First recorded in 1875–80

Words Nearby principal axis

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use principal axis in a sentence

  • These are at points on the principal axis that are twice as far from O, the center of the lens, as are the principal foci.

    Physics | Willis Eugene Tower
  • In the stauraxonia the vertical imaginary principal axis is cut by two or more horizontal cross-axes or radial-axes.

    The Wonders of Life | Ernst Haeckel
  • Direct nitration gives (principally) m-nitrobenzoic acid, also pseudo-tetragonal with a much shorter principal axis.

  • Benzoic acid is pseudo-tetragonal, the principal axis being remarkably long; there is no cleavage at right angles to this axis.

  • The intersection of this last line with the principal axis will give the optical center.

    Visual Signaling | Signal Corps United States Army

British Dictionary definitions for principal axis

principal axis

noun
  1. the line passing through the optical centre and centres of curvature of the faces of a lens or a curved mirror

  2. any of three mutually perpendicular axes about which the moment of inertia of a body is maximum

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012