noun, often capitalized, often attributive
\ˈdē \
plural d's or ds\ ˈdēz \

Definition of

(Entry 1 of 6)

1a : 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 6 sense 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 sense 2b play tough D

b : defense sense 4b


abbreviation (1)

Definition of (Entry 2 of 6)

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 down (see down entry 5 sense 6)

15 drive; driving


abbreviation (2)

Definition of (Entry 3 of 6)

1 Democrat

2 derivative

3 dollar

4 Dutch


symbol (1)

Definition of (Entry 4 of 6)



\ˌdē, ˈdē\

Definition of d- (Entry 5 of 6)

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


symbol (2)

Definition of -d (Entry 6 of 6)

used after the figure 2 or 3 to indicate the ordinal number second or third 2d53d

Examples of d in a Sentence


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.
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First Known Use of d


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

History and Etymology for d


International Scientific Vocabulary, from dextr-

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Dictionary Entries near d

Czech Republic







Statistics for d

Look-up Popularity

Time Traveler for d

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

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More Definitions for d



English Language Learners Definition of d

: 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


noun, often capitalized
\ˈdē \
plural d's or ds\ ˈdēz \

Kids Definition of d

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

Kids Definition of d.

1 day

2 dead

3 deceased

4 penny

Medical Definition of

(Entry 1 of 3)

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



Medical Definition of (Entry 2 of 3)



\ˌdē, ˈdē\

Medical Definition of d- (Entry 3 of 3)

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

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Legal Definition of

1 district

2 defendant

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More from Merriam-Webster on d

See words that rhyme with d

Spanish Central: Translation of d

Nglish: Translation of d for Spanish Speakers

Comments on d

What made you want to look up d? Please tell us where you read or heard it (including the quote, if possible).


to express warning or disapproval

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