deltaとは 意味・読み方・使い方

語源

From Ancient Greek δέλτα (délta), borrowed from a Phoenician word for "door", ultimately from Proto-Semitic *dalt-. Doublet of dalet.

• (river): from the triangular shape of the majuscule Greek letter delta Δ
• (USSF): from the delta wing, symbol of the USSF, a triangular wing, shaped like the majuscule Greek letter delta Δ

発音

• IPA^(key): /ˈdɛltə/, [ˈdɛɫtə]
• 韻: -ɛltə

名詞

delta (複数形 deltas)

1. The fourth letter of the modern Greek alphabet Δ, δ.
2. A landform at the mouth of a river where it empties into a body of water.

   Nile Delta

3. (international standards) Alternative letter-case form of Delta from the NATO/ICAO Phonetic Alphabet.
4. (mathematics) The symbol Δ.
5. (computing, informal) A small but noticeable effect. Compare epsilon.

   This will slow the main code path down, but only by delta.

6. (computing) The set of differences between two versions of a file.

   When you update the file, the system will only save the deltas.

7. (physics, engineering) A change in a quantity, likely from "d" for "difference".

   ΔV - "delta vee"(change in velocity, used in rocketry かつ orbital mechanics)

8. (surveying) The angle subtended at the center of a circular arc.
9. A type of cargo bike that has one wheel in front and two in back.
10. (electrical, often attributive) The closed figure produced by connecting three coils or circuits successively, end for end, especially in a three-phase system.

    delta winding; delta connection; delta current

11. (finance) The rate of change in an option value with respect to the underlying asset's price.
12. (chemistry) A value in delta notation indicating the relative abundances of isotopes.
13. (US, military, U.S. Space Force) A military unit, nominally headed by a colonel, equivalent to a USAF operations wing, or an army regiment.
14. (astronomy) a star that is usually the fourth brightest of a constellation.
15. (physics) one of four baryons consisting of up and down quarks with a combined spin of 3/2: Δ⁺⁺ (uuu), Δ⁺ (uud), Δ⁰ (udd), or Δ⁻ (ddd)
16. (medicine) Short for delta variant. (variant of the SARS-CoV-2 virus)

同意語

• (USSF): garrison (a support wing equivalent)

上位語

• (measure of derivative price sensitivity): Greeks (includes list of coordinate terms)
• (particle physics): baryon; resonance

派生語

参考

• deltoid
• Appendix: IPA examples

動詞

delta (三人称単数 現在形 deltas, 現在分詞 deltaing, 過去形および過去分詞形 deltaed)

1. (cryptography) To calculate the differences between the characters in an enciphered text and the characters a fixed number of positions previous.
   • 2007, B. J. Copeland, “Tunny and Colossus: Breaking the Lorenz Schlüsselzusatz traffic”, in Karl de Leeuw, Jan Bergstra, editors, The History of Information Security: A Comprehensive Handbook, Amsterdam: Elsevier, →ISBN, page 458:

     Turingery worked on deltaed key to produce the deltaed contribution of the chi-wheels. Turing's discovery that delta-ing would reveal information otherwise hidden was essential to the developments that followed.

2. (computing) To compare two versions of the same file in order to determine where they differ (where a programmer has made edits).
   • 1992, Israel Silverberg, Source File Management With SCCS, Englewood Cliffs, NJ: Prentice Hall, →ISBN, page 166:

     The primary function of this command is to delta the product version file (if it has been retrieved for edit). However, prior to deltaing the product version file, the work source tree is searched to verify that no other source files are still waiting to be deltaed.

アナグラム

• Adlet, adlet, atled, dalet, dealt, lated, taled