order of magnitudeとは 意味・読み方・使い方

語源

18th century, in the sense "magnitude (brightness class) of a star", informed by the Greek τῶν μεγάλων τάξις (tôn megálōn táxis) (Ptolemy).

発音

名詞

order of magnitude (plural orders of magnitude)

1. (mathematics) The class of scale or magnitude of any amount, where each class contains values of a fixed ratio (most often 10) to the class preceding it.

   Synonym: OOM (initialism)

   Hypernyms: order, scale

   Hyponym: ROM (“rough order of magnitude”)

   • 2011, Enrico Fermi, Wikisource (translator), Concerning a Contradiction between the Electrodynamic and Relativistic Theory of Electromagnetic Mass, 1922, Enrico Fermi, Über einen Widerspruch zwischen der elektrodynamischen und relativistischen Theorie der elektromagnetischen Masse, Physikalische Zeitschrift, v 23, pp 340-344,

     However, we notice that although this contraction is of order of magnitude ${\displaystyle v^{2}:c^{2}}$, it changes the most important terms of electromagnetic mass, i.e, the rest mass.

   • 2019, Li Huang, James Lambert, “Another Arrow for the Quiver: A New Methodology for Multilingual Researchers”, in Journal of Multilingual and Multicultural Development, →DOI, page 8:

     However, this pales to insignificance against the massive volume of spoken language, for with over 500 patrons, any given second of the lunch hour would result in a spoken word count in the thousands, and the whole lunch hour would see a word count orders of magnitude larger than 3000.

参考

• dex
• ballpark figure (colloquial)