δ

Unicode name

GREEK SMALL LETTER DELTA

Codepoint

γ ←

Greek and Coptic

→ ε

See also Appendix:Variations of "d"

Translingual [edit]

δ

(mathematics) A small increment or change in a variable.

$\delta$ $x$ is a small change in variable $x$
(mathematics, calculus of variations) Denotes a small — rather infinitesimal — variation of the value returned by a functional and/or of the functions on which that functional depends. This symbol can also — along a similar vein — be used to help denote virtual displacement and virtual work.
(mathematics) A small number, usually accompanied by ε.
- For any $\epsilon>0$ , there is a $\delta$ $>0$ …

Derived from its majuscule counterpart Δ, from the Phoenician letter 𐤃, dalet.

δ (lowercase, uppercase Δ)

Lower case delta (δέλτα), the fourth letter of Greek alphabet. It represented in Ancient Greek a voiced dental plosive: IPA: /d/ and in modern Greek a voiced dental fricative: IPA: /ð/. It is preceded by γ and followed by ε.