[ del-tuh ]
/ ˈdɛl tə /
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In effect, this quiz will prove whether or not you have the skills to know the difference between “affect” and “effect.”
Question 1 of 7
The rainy weather could not ________ my elated spirits on my graduation day.

Origin of delta

1350–1400; Middle English deltha<Latin delta<Greek délta; akin to Hebrew dāleth
delta , estuary

Definition for delta (2 of 2)

[ del-tuh ]
/ ˈdɛl tə /

noun Military.

the NATO name for a class of Soviet nuclear-powered ballistic missile submarine armed with 16 multi-warhead missiles.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for delta (1 of 3)

/ (ˈdɛltə) /


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
deltaic (dɛlˈteɪɪk) or deltic, adjective
C16: via Latin from Greek, of Semitic origin; compare Hebrew dāleth

British Dictionary definitions for delta (2 of 3)

/ (ˈdɛltə) /


(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

British Dictionary definitions for delta (3 of 3)

/ (ˈdɛltə) /


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)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for delta (1 of 2)

[ dĕltə ]


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.


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.

Medical definitions for delta (2 of 2)

δ, Δ

The Greek letter delta. Entries beginning with this character are alphabetized under delta.
The symbol fordouble bond
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for delta

[ dĕltə ]

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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