d

1 of 6

noun

plural d's or ds ˈdēz How to pronounce d (audio)
often capitalized, often attributive
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 scale entry 5 sense 1)
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 sense 2b
play tough D

d

2 of 6

abbreviation (1)

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
15
drive; driving

D

3 of 6

abbreviation (2)

1
Democrat
2
derivative
3
dollar
4
Dutch

D

4 of 6

symbol (1)

deuterium

d-

5 of 6

prefix

ˌdē,
ˈdē
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

-d

6 of 6

symbol (2)

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

Examples of d in a Sentence

Noun Many people who are learning to read confuse b's and d's. names that start with d The song is in the key of D. She got a D on her chemistry test.

Word History

Etymology

Prefix

International Scientific Vocabulary, from dextr-

First Known Use

Noun

before the 12th century, in the meaning defined at sense 1a

Time Traveler
The first known use of d was before the 12th century

Dictionary Entries Near d

Cite this Entry

“D.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/d. Accessed 21 Feb. 2024.

Kids Definition

d

noun
ˈdē
plural d's or ds
often capitalized
1
: the fourth letter of the English alphabet
2
: five hundred in Roman numerals see number
3
: the musical note referred to by the letter D : the second tone of the C-major scale
4
: a grade rating a student's work as poor

Medical Definition

d

1 of 3 abbreviation
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

2 of 3 symbol
deuterium

d-

3 of 3 prefix
ˌdē, ˈdē
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

Legal Definition

D

abbreviation
1
district
2
defendant

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