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.

---

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

---

verb

1. (tr) to make concave

concave Scientific  

/ kŏn′kāv′ /

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

---

Other Word Forms

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

Etymology

Origin of concave

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

Example Sentences

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

"To bring this feature to a molecule, I envisioned encapsulating the rotator space by using bulky concave shaped stators."

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

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