Definition of "delta" in 英语

noun

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, physics, engineering) The symbol Δ; A change in a quantity, likely from "d" for "difference".

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

5. (finance) The rate of change in an option value with respect to the underlying asset's price.

6. (chemistry) A value in delta notation indicating the relative abundances of isotopes.

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

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

8. (computing, informal) A small but noticeable effect. Compare epsilon.

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

9. (surveying) The angle subtended at the center of a circular arc.

10. A type of cargo bike that has one wheel in front and two in back.

11. (electricity, 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

12. (US, military, U.S. Space Force) A military unit, nominally headed by a colonel, equivalent to a USAF operations wing, or an army regiment.

13. (astronomy) a star that is usually the fourth brightest of a constellation.

14. (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)

15. (medicine) Ellipsis of delta variant (variant of the SARS-CoV-2 virus).

verb

1. (cryptography) To calculate the differences between the characters in an enciphered text and the characters a fixed number of positions previous.

2. (computing) To compare two versions of the same file in order to determine where they differ (where a programmer has made edits).