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Del·ta

(dĕltə)

An area of the south-central United States extending on either side of the Mississippi River from Memphis, Tennessee, to Vicksburg, Mississippi. An important cotton-producing region, it is noted for its folk culture, especially as the home of some of the earliest blues music.

del·ta

(dĕltə)

1. The fourth letter of the Greek alphabet. See Table at alphabet.

2. An object shaped like a triangle.

a. A usually triangular alluvial deposit at the mouth of a river.

b. A similar deposit at the mouth of a tidal inlet, caused by tidal currents.

4. Mathematics A finite increment in a variable.

adj.
Chemistry

1. Being in the fourth position relative to a designated carbon atom in an organic molecule at which an atom or a group may be substituted.

2. Referring to the fourth of a group of isomers, or molecules of similar origin or properties, determined arbitrarily by those who discover or classify them. Used in combination.

[Middle English, from Latin, from Greek, of Phoenician origin; see dl in the Appendix of Semitic roots.]

del·taic (-tāĭk), deltic (-tĭk) adj.

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delta

satellite image of the

Nile River delta, Egypt

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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