NOUN (3)

1. a low triangular area of alluvial deposits where a river divides before entering a larger body of water;
- Example: "the Mississippi River delta"
- Example: "the Nile delta"

2. an object shaped like an equilateral triangle;

3. the 4th letter of the Greek alphabet;

The Collaborative International Dictionary of English v.0.48:

Delta \Del"ta\, n.; pl. Deltas. [Gr. de`lta, the name of the
   fourth letter of the Greek alphabet (the capital form of
   which is [Delta], Eng. D), from the Ph[oe]nician name of the
   corresponding letter. The Greeks called the alluvial deposit
   at the mouth of the Nile, from its shape, the Delta of the
   Nile.]
   1. The fourth letter of the Greek alphabet ([Delta] [delta]),
      corresponding to D. Hence, an object having the shape of
      the capital [Delta].
      [Webster 1913 Suppl.]

   2. A tract of land shaped like the letter delta ([Delta]),
      especially when the land is alluvial and inclosed between
      two or more mouths of a river; as, the delta of the
      Ganges, of the Nile, or of the Mississippi.
      [1913 Webster]

   3. (Elec.) The closed figure produced by connecting three
      coils or circuits successively, end for end, esp. in a
      three-phase system; -- often used attributively, as delta
      winding, delta connection (which see), etc.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

delta
    n 1: a low triangular area of alluvial deposits where a river
         divides before entering a larger body of water; "the
         Mississippi River delta"; "the Nile delta"
    2: an object shaped like an equilateral triangle
    3: the 4th letter of the Greek alphabet

The Free On-line Dictionary of Computing (19 January 2023):

Delta

   

   1. An expression-based language developed by J.C. Cleaveland
   in 1978.

   2. A string-processing language with single-character commands
   from Tandem Computers.

   3. A language for system specification of simulation
   execution.

   ["System Description and the DELTA Language",
   E. Holback-Hansen et al, DELTA Proj Rep 4, Norweg Comput Ctr,
   Feb 1977].

   4. A COBOL generating language produced by Delta Software
   Entwicklung GmbH (http://delta-software.de/).

   (2000-08-02)


The Free On-line Dictionary of Computing (19 January 2023):

delta
within delta of

   1. A quantitative change, especially a small or incremental
   one (this use is general in physics and engineering).  "I just
   doubled the speed of my program!"  "What was the delta on
   program size?"  "About 30 percent."  (He doubled the speed of
   his program, but increased its size by only 30 percent.)

   2. [Unix] A diff, especially a diff stored under the set
   of version-control tools called SCCS (Source Code Control
   System) or RCS (Revision Control System).  See change
   management.

   3. A small quantity, but not as small as epsilon.  The
   jargon usage of delta and epsilon stems from the
   traditional use of these letters in mathematics for very small
   numerical quantities, particularly in "epsilon-delta" proofs
   in limit theory (as in the differential calculus).  The term
   delta is often used, once epsilon has been mentioned, to
   mean a quantity that is slightly bigger than epsilon but
   still very small.  "The cost isn't epsilon, but it's delta"
   means that the cost isn't totally negligible, but it is
   nevertheless very small.  Common constructions include "within
   delta of ---", "within epsilon of ---": that is, "close to"
   and "even closer to".

   [Jargon File]

   (2000-08-02)


The Jargon File (version 4.4.7, 29 Dec 2003):

delta
 n.

    1. [techspeak] A quantitative change, especially a small or incremental one
    (this use is general in physics and engineering). “I just doubled the speed
    of my program!” “What was the delta on program size?” “About 30 percent.”
    (He doubled the speed of his program, but increased its size by only 30
    percent.)

    2. [Unix] A diff, especially a diff stored under the set of
    version-control tools called SCCS (Source Code Control System) or RCS
    (Revision Control System).

    3. n. A small quantity, but not as small as epsilon. The jargon usage of
    delta and epsilon stems from the traditional use of these letters in
    mathematics for very small numerical quantities, particularly in
    ‘epsilon-delta’ proofs in limit theory (as in the differential calculus).
    The term delta is often used, once epsilon has been mentioned, to mean
    a quantity that is slightly bigger than epsilon but still very small. “
    The cost isn't epsilon, but it's delta” means that the cost isn't totally
    negligible, but it is nevertheless very small. Common constructions include
    within delta of —, within epsilon of —: that is, ‘close to’ and ‘even
    closer to’.