dual

C1 CET-4 Oxf 5000 大学 FREQ #17642 ★★☆☆☆

a. 双重的, 双的 n. 双数

发音

UK /ˈd͡ʒuː.əl/
US /ˈdul/
US /ˈd(j)u.əl/

词形变化

duals 复数 duals dualed dualled dualling duals 三单 dualing 现在分词 dualling 现在分词 dualed 过去式 dualed 过去分词 dualled 过去式 dualled 过去分词

别名

du.

教材释义与例句

名词

双数；双数词

形容词

双的；双重的

释义与例句

n.
  1. 1.

    Of an item that is one of a pair, the other item in the pair.

  2. 2.

    Of a regular polyhedron with V vertices and F faces, the regular polyhedron having F vertices and V faces.

    数学

    The octahedron is the dual of the cube.

  3. 3.

    The dual number.

    语言学
  4. 4.

    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.

    数学
  5. 5.

    A head-to-head match or meet between two teams, such as two high schools or colleges.

    政治 体育 军事
v.
  1. 1.

    To convert from single to dual; specifically, to convert a single-carriageway road to a dual carriageway.

    及物
adj. C1 Oxf 5000
  1. 1.

    Characterized by having two (usually equivalent) components.

    a dual-motor vehicle

  2. 2.

    Pertaining to two, pertaining to a pair of.

    dual engine failure

    dual citizenship

  3. 3.

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

    双数

    语言学

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

  4. 4.

    Exhibiting duality.

    数学 物理
  5. 5.

    Being the space of all linear functionals of (some other space).

    数学
  6. 6.

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

    计算机 工程 数学

词汇关系

形容词

同义词 5

double treble threefold duple twofold

近义相关 2

multiple plural

相关短语

dual carriageway n. <英>（中间有分隔带的）复式车行道 dual meet dual citizenship [法] 双重公民的资格, 双重国籍 dual space dual mandate dual audio dual primary dual boot dual citizenships dual polyhedron dual polyhedra dual mode [计] 对偶方式 dual modes dual spaces dual SIM

词源

PIE word *dwóh₁ Borrowed from Latin dualis (“two”), from duo (“two”) + adjective suffix -alis.

来源：wiktionary