Dictionary.com
Thesaurus.com

plano-concave

American  
[pley-noh-kon-keyv, -kon-keyv] / ˌpleɪ noʊˈkɒn keɪv, -kɒnˈkeɪv /

adjective

Optics.
  1. pertaining to or noting a lens that is plane on one side and concave on the other.


plano-concave British  
/ ˌpleɪnəʊˈkɒnkeɪv /

adjective

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

"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

Etymology

Origin of plano-concave

First recorded in 1685–95; plano- 1 + concave

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Galileo’s telescope consisted of two lenses—one plano-convex, the other plano-concave, the latter being held next the eye.

From The Astronomy of Milton's 'Paradise Lost' by Orchard, Thomas Nathaniel

The names of the various shapes are as follows:—No. 1, plano-convex; No. 2, plano-concave; No. 3, double convex; No. 4, double concave; No. 5, meniscus; No. 6, concavo-convex.

From How it Works Dealing in simple language with steam, electricity, light, heat, sound, hydraulics, optics, etc., and with their applications to apparatus in common use by Williams, Archibald

What Hall and Dollond did was to make the outer or crown lens of the objective as before, and place behind it a plano-concave lens of dense flint glass.

From Astronomy: The Science of the Heavenly Bodies by Todd, David Peck

There, two lenses were made, one plano-convex, and the other plano-concave, and these were placed in a tube made of sheet copper.

From Little Journeys to the Homes of the Great - Volume 12 Little Journeys to the Homes of Great Scientists by Hubbard, Elbert

A. Thoma's Model, plano-concave, with handle adapted for clamping immediately to the knife carrier of the microtome, in box.

From Microscopes and Accessory Apparatus Catalogue No. 40 by Leitz, Ernst