Dualとは 意味・読み方・使い方

別の表記

• du. (abbreviation, grammar)

語源

Borrowed from Latin dualis (“two”), from duo (“two”) + adjective suffix -alis.

発音

• (Received Pronunciation) enPR: dyo͞oʹəl, jo͞oʹəl
  • (yod-coalescence) IPA: /ˈd͡ʒuː.əl/
  • (non-yod-coalescence) IPA: /ˈdjuː.əl/
• (General American) enPR: d(y)o͞o'əl; IPA: /ˈdul/, /ˈd(j)u.əl/
• 異形同音異義語: duel; jewel (yod-coalescence)
• 韻: -uːəl

形容詞

dual (not comparable)

1. Characterized by having two (usually equivalent) components.

   Synonyms: double, twin; see also Thesaurus:dual

   a dual-motor vehicle

2. Pertaining to two, pertaining to a pair of.

   Synonyms: double, duplicate; see also Thesaurus:twofold

   dual engine failure

   dual citizenship

   • 2020, Grace Ying May, “Women Disciplining Men: A Biblical Pattern of Leadership”, in Aída Besançon Spencer, William David Spencer, editors, Christian Egalitarian Leadership: Empowering the Whole Church According to the Scriptures, page 48:

     Both Deborah and Samuel held dual roles as judges and prophets.

   • 2021 March 15, Jessie Yeung, “These Asian countries are giving dual citizens an ultimatum on nationality – and loyalty”, in CNN‎:

     And some Asian countries are tightening their immigration laws. Japan reinforced its strict stance in January when a court upheld the country’s ban against dual citizenship, rejecting a lawsuit filed by Japanese citizens living in Europe.

3. (grammar) Pertaining to a grammatical number in certain languages that refers to two of something, such as a pair of shoes.

   Coordinate terms: singular, trial, plural

   Modern Arabic displays a dual number, as did Homeric Greek.

4. (mathematics, physics) Exhibiting duality.
5. (linear algebra) Being the space of all linear functionals of (some other space).
   • 2012, Doug Fisher, Hans-J. Lenz, Learning from Data: Artificial Intelligence and Statistics V, Springer Science & Business Media, →ISBN, page 81:

     Accordingly, a hyperplane in the sample space is dual to a subspace in the variable space.

6. (category theory) Being the dual of some other category; containing the same objects but with source and target reversed for all morphisms.

   Synonym: opposite

   • 1992, Colin McLarty, Elementary Categories, Elementary Toposes, Clarendon Press, →ISBN, page 77:

     Every category is dual to its own dual, so if a statement holds in all categories so does its dual.

派生語

名詞

dual (plural duals)

1. Of an item that is one of a pair, the other item in the pair.
2. (geometry) Of a regular polyhedron with V vertices and F faces, the regular polyhedron having F vertices and V faces.

   The octahedron is the dual of the cube. The icosahedron is the dual of the dodecahedron.

3. (grammar) The dual number.
4. (mathematics) Of a vector in an inner product space, the linear functional corresponding to taking the inner product with that vector. The set of all duals is a vector space called the dual space.
5. (wrestling) A head-to-head match or meet between two teams, such as two high schools or colleges.
   • 2010 August 3, Kevin Revolinski, Insiders' Guide® to Madison, WI, Rowman & Littlefield, →ISBN, page 137:

     Wrestling duals and meets take place at the Wisconsin Field House. There are no advance single event ticket sales.

   • 2014 November 18, Mark Schultz, David Thomas, Foxcatcher: The True Story of My Brother's Murder, John du Pont's Madness, and the Quest for Olympic Gold, Penguin, →ISBN:

     But Dave agreed to participate in the Bulgarian dual, and that trapped me into having to wrestle, too.

   • 2023 October 19, Jason Norman, American Women in Amateur Wrestling, 2000-2022, McFarland, →ISBN, page 203:

     Early in 2021, she became the first female to compete and win a match at the Ter-Hark Cup wrestling dual, helping her squad to victory.

派生語

参考

• (grammatical numbers) grammatical number; singular, dual, trial, quadral, quintal, paucal, plural
• unal
• duel

動詞

dual (third-person singular simple present duals, present participle (US) dualing or (UK) dualling, simple past and past participle (US) dualed or (UK) dualled)

1. (transitive) To convert from single to dual; specifically, to convert a single-carriageway road to a dual carriageway.
   • 1994, Great Britain. Parliament. House of Commons, Parliamentary Debates:

     I have to declare an interest and I do so with some ambivalence because if the road is dualled it is likely to take half of my front garden.

   • 2006, David Lowe, Intermodal Freight Transport, page 163:

     The power generation and propulsion systems are dualled to accommodate component failure and maintain propulsion at reduced speed should any part of one system be lost.

   • 2021 September 22, “Network News: Nexus increases Tyne and Wear Metro train order to 46”, in RAIL, number 940, page 23:

     The investment will allow Nexus to increase service frequencies, reduce journey times, and improve reliability by dualling three sections of line between Pelaw and South Shields.

アナグラム

• Auld, Daul, Dula, auld, laud, udal