dualとは意味・読み方・使い方

語源

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

発音

• (英国発音) enPR: dyo͞oʹəl, jo͞oʹəl; IPA^(key): /ˈdjuː.əl/, /ˈdʒuː.əl/
• (米国発音) enPR: d(y)o͞o'əl; IPA^(key): /ˈd(j)u.əl/
• 韻: -ʊəl
• Homophone: duel

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, editor, Christian Egalitarian Leadership: Empowering the Whole Church According to the Scriptures, page 48:

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

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 (複数形 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.

3. (Can we clean up⁽⁺⁾ this sense?) (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.

派生語

参考

• (grammatical numbers) grammatical number; singular, dual, trial, quadral, paucal, plural ^{(Category: en:Grammar)}
• unal
• duel

動詞

dual (third-person singular simple present duals, present participle (英国用法) dualling or (米国用法) dualing, simple past and past participle (英国用法) dualled or (米国用法) dualed)

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, p. 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