Meaning of DELTA in English

I. ˈdeltə noun

( -s )

Etymology: Middle English deltha, from Greek delta, of Semitic origin; akin to Hebrew dāleth 4th letter of the Hebrew alphabet — more at daleth

1. : the fourth letter of the Greek alphabet — symbol Δ or δ; see alphabet table

2. : any of various things felt to resemble a capital Δ: as

a. : the alluvial deposit at the mouth of a river commonly forming a nearly flat fan-shaped plain of considerable area traversed by many separate branches in which the river distributes itself downstream and resulting from the accumulation of stream-borne sediment supplied more rapidly than it can be carried away by offshore and alongshore currents

b. : the closed figure produced by connecting three electrical coils or circuits successively end for end especially in a three-phase system

c. : the triangular terminus of a pattern in a fingerprint formed either by bifurcation of a ridge or by divergence of two ridges that are parallel beyond it

3. : an increment of a variable — symbol Δ


Usage: usually capitalized

— a communications code word for the letter d

III. adjective

or δ- “

1. : of or relating to one of four or more closely related chemical substances


— used somewhat arbitrarily to specify ordinal relationship or to specify a particular physical form, especially an allotropic modification (as in δ-iron), or an isomeric or stereoisomeric form (as in δ-benzene hexachloride)

2. : fourth in position in the structure of an organic molecule from a particular group or atom or having a structure characterized by such a position

δ-hydroxy acids


3. : fourth in order of brightness — used of a star in a constellation

IV. adjective

Usage: often capitalized

: of, relating to, or characteristic of the region of the alluvial plain east of the Mississippi River in western Mississippi

delta blues

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.