convexとは 意味・読み方・使い方

語源

Borrowed from Middle French convexe, from Latin convexus (“arched”).

発音

• (Received 発音) IPA^(key): /ˈkɒn.vɛks/, /kɒnˈvɛks/, /kənˈvɛks/
• (General American) IPA^(key): /ˈkɑn.vɛks/, /kɑnˈvɛks/, /kənˈvɛks/

形容詞

convex (comparative more convex, superlative most convex)

1. Curved or bowed outward like the outside of a bowl, circle, or sphere.
   • 1837, William Whewell, “Earliest Stages of Astronomy”, in History of the Inductive Sciences, from the Earliest to the Present Times. […], volume I, London: John W[illiam] Parker, […]; Cambridge, Cambridgeshire: J. and J. J. Deighton, OCLC 1112872753, book III (History of Greek Astronomy), section 9 (The Globular Form of the Earth), page 150:

     [D]rops of water naturally form themselves into figures with a convex surface; […]

2. (functional analysis, not comparable, of a real-valued function on the reals) having an epigraph that is a convex set.
3. (geometry, not comparable, of a polygon) having no internal angles greater than 180 degrees.
4. (mathematics, not comparable, of a set in Euclidean space) arranged such that for any two points in the set, a straight line between the two points is contained within the set.

反意語

• concave

派生語

名詞

convex (複数形 convexes)

1. Any convex body or surface.
   • 1714, Thomas Tickell, Royal Progress

     Half heaven's convex glitters with the flame.

2. (gambling) A playing card made convex for use in cheating.

   Coordinate term: concave

3. (gambling) A small convex mirror used to cheat by observing other players' cards.

   Synonym: shiner

   • 2019, John Philip Quinn, Fools of Fortune; or, Gambling and Gamblers

     Of all the devices for defrauding at poker, the “shiner,” or “convex” […] Modern convexes are also considerably larger than those of former days.

参照

• “convex”, in The Oxford English Dictionary, 2nd edition, Oxford: Clarendon Press, 1989, →ISBN.