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.
3. The letter D in the ICAO spelling alphabet, which assigns words to letters of the alphabet.
4. δ In the IPA, the symbol that represents the voiced dental fricative, the hard th in the English word father; frequently represented by the Icelandic eth (ð).
5. The symbol Δ.
6. A small but noticeable effect, compare with epsilon.

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

7. The set of differences between two versions of a file.

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

8. The angle subtended at the center of a circular arc.