noun
- the fourth letter of the Greek alphabet (Δ, δ).
- the consonant sound represented by this letter.
- the fourth in a series of items.
- anything triangular, like the Greek capital delta (Δ).
- Mathematics. an incremental change in a variable, as Δ or δ.
- a nearly flat plain of alluvial deposit between diverging branches of the mouth of a river, often, though not necessarily, triangular: the Nile delta.
- (usually initial capital letter) a word used in communications to represent the letter D.
- (initial capital letter) Astronomy. a star that is usually the fourth brightest of a constellation: The fourth brightest star in the Southern Cross is Delta Crucis.
noun Military.
- the NATO name for a class of Soviet nuclear-powered ballistic missile submarine armed with 16 multi-warhead missiles.
noun
- the fourth letter in the Greek alphabet (Δ, δ), a consonant transliterated as d
- an object resembling a capital delta in shape
- (capital when part of name) the flat alluvial area at the mouth of some rivers where the mainstream splits up into several distributariesthe Mississippi Delta
- maths a finite increment in a variable
noun
- (foll by the genitive case of a specified constellation) usually the fourth brightest star in a constellation
- any of a group of US launch vehicles used to put unmanned satellites into orbit
- communications a code word for the letter d
noun
- a state of Nigeria, on the Niger river delta on the Gulf of Guinea. Capital: Asaba. Pop: 4 098 391 (2006). Area: 17 698 sq km (6833 sq miles)
c.1200, Greek letter shaped like a triangle, equivalent to our “D,” the name from Phoenician daleth “tent door.” Herodotus used it of the mouth of the Nile, and it was so used in English from 1550s; applied to other river mouths from 1790.
n.
- The fourth letter of the Greek alphabet.
- The fourth one in a series.
- A surface or part that resembles a triangle, such as the terminus of a pattern in a fingerprint or the shape of a muscle.
adj.
- Of or characterizing the atom or radical group that is fourth in position from the functional group of atoms in an organic molecule.
- Of or relating to one of four closely related chemical substances.
- Relating to or characterizing a polypeptide chain that is one of five types of heavy chains present in immunoglobins.
- A usually triangular mass of sediment, especially silt and sand, deposited at the mouth of a river. Deltas form when a river flows into a body of standing water, such as a sea or lake, and deposits large quantities of sediment. They are usually crossed by numerous streams and channels and have exposed as well as submerged areas.