concave

American  

[kon-keyv, kon-keyv, kon-keyv] / kɒnˈkeɪv, ˈkɒn keɪv, ˈkɒn keɪv /

adjective

1. curved like a segment of the interior of a circle or hollow sphere; hollow and curved.

2. Geometry. (of a polygon) having at least one interior angle greater than 180°.

3. Obsolete. hollow.

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noun

1. a concave surface, part, line, or thing.

2. Machinery. a concave piece, as one against which a drum rotates.

verb (used with object)

concaved, concaving

1. to make concave.

concave British  

/ ˈkɒnkeɪv, kɒnˈkeɪv /

adjective

1. curving inwards

2. 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

3. maths (of a polygon) containing an interior angle greater than 180°

4. an obsolete word for hollow

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verb

1. (tr) to make concave

concave Scientific  

/ kŏn′kāv′ /

1. Curved inward, like the inside of a circle or sphere.

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Other Word Forms

• concaveness
  noun
• subconcaveness
  noun
• subconcave
  adjective
• concavely
  adverb
• subconcavely
  adverb

Etymology

Origin of concave

1375–1425; late Middle English (< Middle French ) < Latin concavus, hollow. See con-, cave

Explanation

Concave describes an inward curve; its opposite, convex, describes a curve that bulges outward. They are used to describe gentle, subtle curves, like the kinds found in mirrors or lenses. A valley is a concave curve, a mountain is a convex curve—you can remember this by thinking that things that vex you tend to stick out, and that caves tend to be holes that go in, like valleys or innie belly buttons. If you want to describe a bowl, you might say there is a large blue spot on the center of the concave side.

Example Sentences

See Examples For:

concave concaved concaving

It only uses 1.0 gpf, with the help of two strong jets concealed in a concave rim beneath the seat that create a strong swirl during the flush.

From Slate ● Feb. 25, 2025

It was a little bit concave, like a bowl.

From Science Daily ● Dec. 7, 2023

On the top and bottom of the cylinder, the metal had been pushed up in a concave shape, thrust out from pressure on the inside.

From Los Angeles Times ● Aug. 3, 2023

The "Walkie Talkie" skyscraper attracted controversy in 2013 when sunlight reflected off its mirrored concave side and melted various parts on a luxury car parked nearby.

From BBC ● Mar. 4, 2023

Fixed to the front of it was something that looked like a fencing mask, with the concave side outwards.

From "1984" by George Orwell

In the second book of his Dark Star trilogy, James coaxes beauty from dark thoughts, leaving readers with a concaved, mystical and African-inspired world that begins in free-fall.

From Los Angeles Times ● Feb. 15, 2022

Note that the rear margin of the flukes of this species, unlike that of the humpback whale, is smooth, broad, and concaved distinctly towards a deep fluke notch.

From Whales, Dolphins, and Porpoises of the Western North Atlantic A Guide to Their Identification by David Caldwell

Typewriter faces are not flat like printing type, but are concaved to conform to the curve of the printing surface of the roller.

From The Ear in the Wall by Arthur B. (Arthur Benjamin) Reeve

The flukes of humpback whales show varying amounts of white beneath, are pointed on the tips, and are distinctly concaved and irregularly rippled on the rear margin.

From Whales, Dolphins, and Porpoises of the Western North Atlantic A Guide to Their Identification by David Caldwell

As pointed out elsewhere, it cannot be the concaved type of wing, or its shape, or relative size to the weight it must carry.

From Aeroplanes by James Slough Zerbe

The world below looked like a vast, shallow bowl, the sides concaving upwards around him to the horizon.

From Hoof and Claw by Sir Charles George Douglas Roberts