Etymology 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
The fourth letter of the modern Greek alphabet Δ, δ.
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A landform at the mouth of a river where it empties into a body of water.
Nile Delta
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Alternative letter-case form of Delta from the NATO/ICAO Phonetic Alphabet.
International standards
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Engineering, Mathematics, Natural sciences, Physical sciences, Physics, Sciences 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)
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Business, Finance The rate of change in an option value with respect to the underlying asset's price.
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Chemistry, Natural sciences, Physical sciences A value in delta notation indicating the relative abundances of isotopes.
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Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences The set of differences between two versions of a file.
When you update the file, the system will only save the deltas.
Government, Military, Politics, WarSpace Force, US A military unit, nominally headed by a colonel, equivalent to a USAF operations wing, or an army regiment.
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Astronomy, Natural sciences a star that is usually the fourth brightest of a constellation.
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Natural sciences, Physical sciences, 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)
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Medicine, SciencesAbbreviation, Ellipsis Ellipsis of delta variant (variant of the SARS-CoV-2 virus).
Etymology 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
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Computing, Cryptography, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences To calculate the differences between the characters in an enciphered text and the characters a fixed number of positions previous.
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.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:
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Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences To compare two versions of the same file in order to determine where they differ (where a programmer has made edits).
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.1992, Israel Silverberg, Source File Management With SCCS, Englewood Cliffs, NJ: Prentice Hall, →ISBN, page 166:
Delta
noun
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The Delta variant of COVID-19.
Delta is moderately resistant to vaccines, particularly in people who have received just a single dose.2021 June 22, “Delta coronavirus variant: scientists brace for impact”, in Nature: