Concave
['kɒnkeɪv] or [kɑn'kev]
Definition
(a.) 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.
(a.) Hollow; void of contents.
(n.) A hollow; an arched vault; a cavity; a recess.
(n.) A curved sheath or breasting for a revolving cylinder or roll.
(v. t.) To make hollow or concave.
Edited by Julia
Synonyms and Synonymous
a. Hollow, rounded.
Editor: Margie
Synonyms and Antonyms
SYN:Hollow, scooped, pitted, excavated, retreating, alveolar
ANT:Convex, tumular, protuberant, relievant, embossed, intumescent
Checked by Edwin
Definition
adj. curved vaulted or arched applied to the inner side of any curved line or rounded body and opposed to convex which is applied to the outside.—n. a hollow: an arch or vault.—adv. Con′cavely.—n. Concav′ity the quality of being concave: the inner surface of a concave or hollow body.—adjs. Concā′vo-con′cave or Doub′le-con′cave concave on both sides of a lens; Concā′vo-con′vex concave on one side and convex on the other.
Editor: Stu
Examples
- K is the cathode plate, formed of a concave disk of aluminum, which focuses the rays at a point near the center of the bulb. Edward W. Byrn. The Progress of Invention in the Nineteenth Century.
- The other is a pad made of aluminum which is concave on one side and convex on the other and may be used in a wet pack. Various. The Wonder Book of Knowledge.
- This monster ship has been built on what is called the wave principle of ship-building, with long concave bows. Frederick C. Bakewell. Great Facts.
- The stalagmites were all a little concave, and the cavities were filled with water. Ulysses S. Grant. Personal Memoirs of U. S. Grant.
- The last three types, called concave lenses, scatter parallel rays so that they do not come to a focus, but diverge widely after passage through the lens. Bertha M. Clark. General Science.
- Nearsightedness can be remedied by wearing concave glasses, since they separate the light and move the focus farther away. Bertha M. Clark. General Science.
- The defect is remedied by concave glasses. Bertha M. Clark. General Science.
- You will perceive, Watson, that the glasses are concave and of unusual strength. Arthur Conan Doyle. The Return of Sherlock Holmes.
- The object of using a concave mirror was to be able to concentrate a greater number of the rays of light than could be done by a lens, and thus to form a brighter image. Frederick C. Bakewell. Great Facts.
- At the pit end, the chute is solidly constructed with a concave flanged surface placed on the top of the kick-back. Various. The Wonder Book of Knowledge.
- It cannot depend on one, for that must be either convex, or concave, or plain. Rupert S. Holland. Historic Inventions.
- T ry a concave glass with the sun's rays to see whether a diminution of heat results. Walter Libby. An Introduction to the History of Science.
- The last form neither augments nor diminishes visible objects; the concave diminishes them, the convex increases them, but both show them blurred and indistinct. Rupert S. Holland. Historic Inventions.
- Concave glasses, by separating the rays and making the focus more distant, overbalance a wide eyeball with its tendency to focus objects in front of the retina. Bertha M. Clark. General Science.
- The gutters are the concave boards that extend the complete length of the alley, from the foul line to the pit, on both sides of the bed. Various. The Wonder Book of Knowledge.
Edited by Barbie