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

形容詞

dual (not comparable)

1. Exhibiting duality; characterized by having two (usually equivalent) components.
2. Acting as a counterpart.
3. Double.

   a dual-headed computer

4. (grammar) Pertaining to grammatical number (as in 単数形 かつ plural), referring to two of something, such as a pair of shoes, in the context of the singular, plural and, in some languages, trial grammatical number.

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

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.
   • 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.

同意語

• (having two components): double, twin; see also Thesaurus:dual
• (double): double, duplicate; see also Thesaurus:twofold
• (category theory): opposite

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. (grammar) dual number The grammatical number of a noun marking two of something (as in 単数形, dual, plural), sometimes referring to two of anything (a couple of, exactly two of), or a chirality-marked pair (as in left かつ right, as with gloves または shoes) or in some languages as a discourse marker, "between you and me". A few languages display trial 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.

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.

   • 1998, Great Britain. Parliament. House of Commons, Parliamentary Debates

     Way back in 1971, the Government of the day first published plans for a high-capacity road network, which included the dualling of the A47 from King's Lynn to Great Yarmouth.

   • 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.

アナグラム

• Auld, Daul, Dula, auld, laud, udal