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

“My chest was concave trying to pull in breath.”

From BBC ● Oct. 10, 2024

The team synthesized concave, umbrella-like metal complexes that could shield the rotor molecule from unwanted interactions with other molecules in the crystal.

From Science Daily ● Sep. 29, 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

Only his brain moved, wet and heavy against the contours of his skull, favoring curvatures of bone and concave niches.

From "Ceremony:" by Leslie Marmon Silko

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

In the eyes now glaring at them malevolently through heavily concaved spectacles they read hate unutterable.

From Astounding Stories of Super-Science, March 1930 by Harry Bates

If a button is much concaved, the pin may be placed underneath.

From Textiles and Clothing by Kate Heintz Watson

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 David Caldwell

San Francisco’s magnificent municipal building had concaved like an egg shell.

From Complete Story of the San Francisco Horror by Richard Linthicum

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