noun del·ta \ˈdel-tə\

: the fourth letter of the Greek alphabet

: a piece of land shaped like a triangle that is formed when a river splits into smaller rivers before it flows into an ocean

: an area of low land along the Mississippi River that is mainly in the state of Mississippi

Full Definition of DELTA

:  the 4th letter of the Greek alphabet — see alphabet table
:  something shaped like a capital Greek delta; especially :  the alluvial deposit at the mouth of a river
:  an increment of a variable —symbol Δ
del·ta·ic \del-ˈtā-ik\ adjective

Origin of DELTA

Middle English deltha, from Greek delta, of Semitic origin; akin to Hebrew dāleth daleth
First Known Use: 13th century

Other Geology Terms

anthracite, boulder, cwm, erratic, igneous, intrusive, mesa, sedimentary, silt, swale



Definition of DELTA

:  fourth in position in the structure of an organic molecule from a particular group or atom —symbol δδ

First Known Use of DELTA

circa 1929

Other Chemical Engineering Terms

alkali, cation, decant, hygroscopic, isotope, oxidize, slurry, solute, viscous


Definition of DELTA

—a communications code word for the letter d

First Known Use of DELTA



geographical name Del·ta \ˈdel-tə\

Definition of DELTA

municipality Canada in SW British Columbia pop 99,863
DELTAIC Defined for Kids


noun del·ta \ˈdel-tə\

Definition of DELTA for Kids

:  a piece of land in the shape of a triangle or fan made by deposits of mud and sand at the mouth of a river


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