1

d

noun, often capitalized, often attributive \ ˈdē \

Definition of d

plural d's or ds play \ˈdēz\
1 a :the 4th letter of the English alphabet
  • Her middle initial is d.
b :a graphic representation of this letter
  • a half moon in the shape of a d
c linguistics :the speech sound that the written letter d represents :a speech counterpart of orthographic d
2 Roman numerals :five hundred — see Table of Numbers
3 music :the second tone of a C-major scale (see 6scale 2)
  • in the key of d
4 :a graphic device for reproducing the letter d
  • the d on my computer keyboard
5 :one designated d especially as the fourth in order or class
  • option d
6 education
a :a grade rating a student's work as poor in quality
  • got a d on the test
b :one graded or rated with a D
7 :something shaped like the letter D; specifically :a semicircle on a pool table about 23 inches in diameter for use especially in snooker
8 capitalized sports
a :defense 2b
  • play tough D
b :defense 4b

Examples of d in a Sentence

  1. Many people who are learning to read confuse b's and d's.

  2. names that start with d

  3. The song is in the key of D.

  4. She got a D on her chemistry test.

First Known Use of d

before 12th century

Other Alphabet Terms


2

d

abbreviation

Definition of d

1 date
2 daughter
3 day
4 dead; deceased
5 deci-
6 degree
7
[Latin denarius, denarii]
penny; pence
8 depart; departure
9 diameter
10 differential
11 dimensional
12 distance
13 dorsal
14 drive; driving

1

D

abbreviation

Definition of D

1 Democrat
2 derivative
3 dollar
4 Dutch

2

D

symbol

Definition of D

deuterium

d-

prefix \ ˌdē , ˈdē \

Definition of d-

1 :dextrorotatory
  • d-tartaric acid
2 :having a similar configuration at a selected carbon atom to the configuration of dextrorotatory glyceraldehyde usually printed as a small capital
  • d-fructose

Origin and Etymology of d-

International Scientific Vocabulary, from dextr-


-d

symbol

Definition of -d

used after the figure 2 or 3 to indicate the ordinal number second or third
  • 2d
  • 53d

D Defined for English Language Learners

d

noun

Definition of d for English Language Learners

  • : the fourth letter of the English alphabet

  • : a musical note or key referred to by the letter D : the second tone of a C-major scale

  • : a grade that is given to a student for doing poor work


D Defined for Kids

d

noun, often capitalized \ ˈdē \

Definition of d for Students

plural d's or ds \ˈdēz\
1 :the fourth letter of the English alphabet
2 :500 in Roman numerals
3 :a grade that shows a student's work is poor
4 :a musical note referred to by the letter D

d.

abbreviation

Definition of d. for Students

1 day
2 dead
3 deceased
4 penny

Medical Dictionary

d

abbreviation

medical Definition of d

1 dalton
2 date
3 daughter
4 day
5 dead
6 deceased
7 deciduous
8 degree
9 density
10 developed
11 deviation
12 dexter
13 diameter
14 died
15 diopter
16 disease
17 divorced
18 dorsal
19 dose
20 duration

D

symbol

medical Definition of D

deuterium

d-

prefix \ ˌdē, ˈdē \

medical Definition of d-

1 :dextrorotatory usually printed in italic
  • d-tartaric acid
2 :having a similar configuration at a selected carbon atom to the configuration of dextrorotatory glyceraldehyde usually printed as a small capital
  • D-fructose

Law Dictionary

D

abbreviation

legal Definition of D

1 district
2 defendant

Learn More about d


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