CONCAVE

concave

(adjective) curving inward

Source: WordNet® 3.1


Etymology

Adjective

concave (comparative more concave, superlative most concave)

curved like the inner surface of a sphere or bowl

(geometry, not comparable, of a polygon) not convex; having at least one internal angle greater than 180 degrees.

(functional analysis, not comparable, of a real-valued function on the reals) satisfying the property that all segments connecting two points on the function's graph lie below the function.

hollow; empty

Antonyms

• convex

Noun

concave (plural concaves)

A concave surface or curve.

The vault of the sky.

One of the celestial spheres of the Ptolemaic or geocentric model of the world.

(manufacturing) An element of a curved grid used to separate desirable material from tailings or chaff in mining and harvesting.

(surfing) An indentation running along the base of a surfboard, intended to increase lift.

(skateboarding) An indented area on the top of a skateboard, providing a position for foot placement and increasing board strength.

Verb

concave (third-person singular simple present concaves, present participle concaving, simple past and past participle concaved)

To render concave, or increase the degree of concavity.

Source: Wiktionary


Con"cave ( or ; 277), a. Etym: [L. concavus; con- + cavus hollow: cf. F. concave. See Cave a hollow.]

1. Hollow and curved or rounded; vaulted; -- said of the interior of a curved surface or line, as of the curve of the of the inner surface of an eggshell, in opposition to convex; as, a concave mirror; the concave arch of the sky.

2. Hollow; void of contents. [R.] As concave . . . as a worm-eaten nut. Shak.

Con"cave, n. Etym: [L. concavum.]

1. A hollow; an arched vault; a cavity; a recess. Up to the fiery concave towering hight. Milton.

2. (Mech.)

Definition: A curved sheath or breasting for a revolving cylinder or roll.

Con"cave, v. t. [imp. & p. p. concaved (; p. pr.& vb. n. Concaving.]

Definition: To make hollow or concave.

Source: Webster’s Unabridged Dictionary 1913 Edition



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Word of the Day

9 May 2025

RIGHT

(noun) anything in accord with principles of justice; “he feels he is in the right”; “the rightfulness of his claim”


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Coffee Trivia

According to Guinness World Records, the largest collection of coffee pots belongs to Robert Dahl (Germany) and consists of 27,390 coffee pots as of 2 November 2012, in Rövershagen, Germany.

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