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 Pronunciation) IPA: /ˈkɒn.vɛks/, /kɒnˈvɛks/, /kənˈvɛks/
• (General American) IPA: /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, 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 (plural convexes)

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

     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.

動詞

convex (third-person singular simple present convexes, present participle convexing, simple past and past participle convexed)

1. (intransitive) To form a convex curve or surface; to become convex.
   • 1859 November, “Harbours of Refuge”, in The United Service Magazine, page 347:

     In like manner the north pier will convex seaward, extending across the bay to the extent of 1000 feet from low water, terminating in about eight fathoms, leaving a clear entrance of 500 feet between the pier heads, the depth of the entrance being from seven to eight fathoms.

   • 1926, David Louis Jones, Diesel Engines, Marine--locomotive--stationary, page 502:

     If the valve is ground excessively, the surfaces of the valve and cage will convex so that the sealing contact is poor.

   • 1998, James Stephen Hardy, Stephen T. Hardy, Time-saver Details for Roof Design, page 247:

     With thin metal flashing, as it expands, the metal between the fasteners will convex.

2. (transitive) To cause to form a convex curve or surface; to make convex.
   • 1898 March, Junius, “Tension in Saws”, in The Wood-worker, volume 17, number 1, page 24:

     The back edge of the saw being under the lip of the cleat, use the anvil for a fulcrum and press down on the edge of the saw opposite, which will convex the plate, as the springing up concaved it, and the action of the fast and loose will be the reverse; that is, the fast will go down and the loose come up.

   • 1945, John Northern Hilliard, Card Magic: A Practical Treatise on Modern Card Conjuring, page 19:

     This will convex the fan and hold the cards more rigidly in place.

   • 2012, Tamir Greenberg, “Elegy”, in Poets on the Edge: An Anthology of Contemporary Hebrew Poetry, page 295:

     In one moment the body will convex the checkered blanket, and later—the featureless absence;

3. (ambitransitive) To circulate or cause to circulate in a curved path; to cause or exhibit convection.
   • 2011, Comprehensive Semiconductor Science and Technology, page 156:

     The crystal/melt interface thus convexes into the melt; however, the convexity of the interface ( Figure 53 ) is not as strong as it is when the crucible does not rotate (Figure 52).

   • 2014, Amy-Elyse Neer, The Seven Things Cookbook, page 96:

     The lid on will convex the heat and you'll need that after it's been chilled.

参照

• John A. Simpson and Edmund S. C. Weiner, editors (1989), “convex”, in The Oxford English Dictionary, 2nd edition, Oxford: Clarendon Press, →ISBN.