algebraとは 意味・読み方・使い方

語源

Borrowed from Medieval Latin algebra, from the Arabic word الْجَبْر (al-jabr, “reunion, resetting of broken parts”) in the title of al-Khwarizmi's influential work الْكِتَاب الْمُخْتَصَر فِي حِسَاب الْجَبْر وَالْمُقَابَلَة (al-kitāb al-muḵtaṣar fī ḥisāb al-jabr wa-l-muqābala, “The Compendious Book on Calculation by Completion and Balancing”).

発音

• (英国発音) IPA: /ˈæl.dʒɪ.bɹə/
• (米国発音) IPA: /ˈæl.d͡ʒɪ.bɹə/, /ˈæl.d͡ʒə.bɹə/
• (Indic) IPA: /əlˈdʒibrɑ/, /-ˈdʒe-/, /-ˈdʒɛ-/

名詞

algebra (countable and uncountable, plural algebras)

1. (uncountable, mathematics) Elementary algebra: A system for representing and manipulating unknown quantities (variables) in equations.
   • 1551, James A.H. Murray, editor, A New English Dictionary on Historical Principles: Founded Mainly on the Materials Collected by the Philological Society.‎, volume 1, Oxford: Clarendon Press, published 1888, Part 1, page 217:

     Also the rule of false position, with dyuers examples not only vulgar, but some appertaynyng to the rule of Algeber.

   • 1854, George Boole, “Signs and their Laws”, in An Investigation of the Laws of Thought, on which are Founded the Mathematical Theories of Logic and Probabilities‎, London: Walton and Maberly, page 37:

     Let us conceive, then, of an Algebra in which the symbols x, y, z, &c. admit indifferently of the values 0 and 1, and of these values alone.

2. (uncountable, mathematics, sometimes capitalized) Abstract algebra: A broad field of study in modern mathematics (often mentioned alongside analysis) loosely characterized by its concern for abstraction and symmetry, dealing with the behavior, classification, and application of a large class of objects (called algebraic structures) and the maps between them (called, most generally, morphisms).
3. (countable, mathematics, algebra) Any of several objects of study in Algebra
   1. A universal algebra.
   2. An algebraic structure consisting of a module over a commutative ring (or a vector space over a field) along with an additional binary operation that is bilinear over module (or vector) addition and scalar multiplication.

      Synonyms: algebra over a field, algebra over a ring

4. (countable, set theory, mathematical analysis) A collection of subsets of a given set, such that this collection contains the empty set, and the collection is closed under unions and complements (and thereby also under intersections and differences).

   Synonyms: field of sets, algebra of sets

   Hypernym: ring

   Hyponym: σ-algebra

5. (figurative) A system or process (especially one that is complex or convoluted) that substitutes one thing for another, or uses signs or symbols to represent concepts or ideas.
   • 1663, William Clark, edited by William Hugh Logan, Marciano; or, The discovery: A tragi-comedy‎, Edinburgh: Reprinted for Private Circulation, published 1871, →ISBN, page 13:

     Fly ! Fly ! avaunt with that base cowardly gibbrish ; That Algebra of honour ; which had never Been nam'd, if all had equal courage—what?

6. (uncountable, medicine, historical, rare) The surgical treatment of a dislocated or fractured bone. Also (countable): a dislocation or fracture.
   • a1420, The British Museum Additional MS, 12,056, “Wounds complicated by the Dislocation of a Bone”, in Robert von Fleischhacker, editor, Lanfranc's "Science of cirurgie."‎, London: K. Paul, Trench, Trübner & Co, translation of original by Lanfranc of Milan, published 1894, →ISBN, page 63:

     Ne take noon hede to brynge togidere þe parties of þe boon þat is to-broken or dislocate, til viij. daies ben goon in þe wyntir, & v. in þe somer; for þanne it schal make quytture, and be sikir from swellynge; & þanne brynge togidere þe brynkis eiþer þe disiuncture after þe techynge þat schal be seid in þe chapitle of algebra.

   • 1987, John Newsome Crossley, “Latency”, in The emergence of number‎, Singapore: World Scientific, →ISBN, Al-Khwarizwi, page 65:

     Algebra is used today by surgeons to mean bone-setting, i.e. the restoration of bones, and the idea of restoration is present in the mathematical context, too.

派生語

関連する語

派生した語

• ⇒ Chinese: 代數 / 代数 (dàishù)
  • → Japanese: 代数
  • → Korean: 대수 (daesu)
  • → Vietnamese: đại số

アナグラム

• Labarge

発音

• (Classical Latin) IPA: [ˈaɫ.ɡɛ.bra]
• (modern Italianate Ecclesiastical) IPA: [ˈal̠ʲ.d͡ʒe.bra]

名詞

algebra f (genitive algebrae); first declension

1. (Medieval Latin, New Latin) algebra

語形変化

First-declension noun.

派生した語

参照

• "algebra", in Charles du Fresne du Cange, Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)