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[adj., v. kon-keyv, kon-keyv; n. kon-keyv] /adj., v. kɒnˈkeɪv, ˈkɒn keɪv; n. ˈkɒn keɪv/
curved like a segment of the interior of a circle or hollow sphere; hollow and curved.
Compare convex (def 1).
Geometry. (of a polygon) having at least one interior angle greater than 180°.
Obsolete, hollow.
a concave surface, part, line, or thing.
Machinery. a concave piece, as one against which a drum rotates.
verb (used with object), concaved, concaving.
to make concave.
Origin of concave
late Middle English
1375-1425; late Middle English (< Middle French) < Latin concavus, hollow. See con-, cave
Related forms
concavely, adverb
concaveness, noun
subconcave, adjective
subconcavely, adverb
subconcaveness, noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for concave
  • Geodesic surfaces can be curved, zig-zag, concave-convex with each other in space.
  • The skull fragment also bore a concave imprint suggestive of a musket ball.
  • The articulating frame may also be configured to cause concave depressions similar to mechanical key caps in the surface.
  • Solid rubber outsole with concave lugs provide all-terrain grip and traction.
  • The concave buttons on the top are difficult to distinguish.
  • Cove molding has only one curve forming a concave profile.
  • They come in nine positive-negative pairs: one with a convex top and a drainage trough around the rim, the other concave.
  • concave interior surfaces add to a sense of spaciousness.
  • Where the ablution room is convex, the school curve is concave.
  • Good pans have a slightly concave bottom that flattens out when heated.
British Dictionary definitions for concave


/ˈkɒnkeɪv; kɒnˈkeɪv/
curving inwards
(physics) having one or two surfaces curved or ground in the shape of a section of the interior of a sphere, paraboloid, etc: a concave lens
(maths) (of a polygon) containing an interior angle greater than 180°
an obsolete word for hollow
(transitive) to make concave
Compare convex
Derived Forms
concavely, adverb
concaveness, noun
Word Origin
C15: from Latin concavus arched, from cavus hollow
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
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Word Origin and History for concave

early 15c., from Old French concave (14c.) or directly from Latin concavus "hollow, arched, vaulted, curved," from com-, intensive prefix (see com-), + cavus "hollow" (see cave (n.)).

Online Etymology Dictionary, © 2010 Douglas Harper
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concave in Medicine

concave con·cave (kŏn-kāv', kŏn'kāv')
Curved like the inner surface of a sphere. n.
A concave surface, structure, or line.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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concave in Science
Curved inward, like the inside of a circle or sphere.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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