• synonyms


[pley-noh-kon-keyv, -kon-keyv]
adjective Optics.
  1. pertaining to or noting a lens that is plane on one side and concave on the other.
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Origin of plano-concave

First recorded in 1685–95; plano-1 + concave
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for plano-concave

Historical Examples

  • If one of the radii becomes infinite, the lens is plano-concave (fig. 9, 5).

    Encyclopaedia Britannica, 11th Edition, Volume 16, Slice 4


  • The achromatic lens consists of a double convex lens of crown glass combined with a plano-concave lens of flint glass.


    Willis Eugene Tower

  • The chromatic combination consists of a convex lens of crown backed by a concave, or plano-concave, lens of flint.

  • Plano-concave and double concave lenses produced similar effects.

British Dictionary definitions for plano-concave


  1. (of a lens) having one side concave and the other side plane
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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