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

Measuring 4.5 meters wide with a concave cross-section, the roads were ideal for stabilizing the statues as they moved forward.

From Science Daily ● Oct. 8, 2025

The digital replica shows that some of the boilers are concave, which suggests they were still operating as they were plunged into the water.

From BBC ● Apr. 8, 2025

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

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

Its hallmark was the “Clovis point,” a four-inch spearhead with a slightly cut-in, concave tail; in silhouette, the points somewhat resemble those goldfish-shaped cocktail crackers.

From "1491" by Charles C. Mann

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

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 Zerbe, James Slough

The head is small relative to the body length and, when viewed laterally, is slightly concaved or scooped on the upper margin.

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

The sides of this nest should be packed hard, the bottom smooth and slightly concaved, not too much, as the tendency then would be to break the eggs if they crowded towards the centre.

From Natural and Artificial Duck Culture by Rankin, James

Dorsal fins of this species may also be rounded on the tip but all are sharply concaved on the rear margin.

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

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

From Hoof and Claw by Roberts, Charles George Douglas, Sir