'd Definition & Meaning

American

British

Scientific

Etymology

Examples

d' 1 American

preposition

1. de (used in French names as an elided form ofde ).

   Charles Louis d'Albert.

2. di (used in Italian names as an elided form ofdi ).

   Gabriele d'Annunzio.

D- 2 American

1. Symbol, Biochemistry. (of a molecule) having a configuration resembling the dextrorotatory isomer of glyceraldehyde: always printed as a small capital, roman character.

D 3 American [dee] / di / Or d

noun

plural

D's, Ds, d's, ds

1. the fourth letter of the English alphabet, a consonant.

2. any spoken sound represented by the letter D or d, as in dog, ladder, ladle, or pulled.

3. something having the shape of a D .

4. a written or printed representation of the letter D or d.

5. a device, as a printer's type, for reproducing the letter D or d.

d. 4 American

abbreviation

1. (in prescriptions) give.

d' 5 American

1. Informal. contraction of do or did before you:

   How d'you like your eggs cooked? D'you go to the movies last night?

d. 6 American

abbreviation

1. British. pence.

D 7 American

abbreviation

1. Electricity. debye; debyes.

2. deep.

3. depth.

4. Optics. diopter.

5. divorced.

6. Dutch.

d- 8 American Symbol, Chemistry, Biochemistry.

1. dextrorotatory; dextro- (l- ).

D. 9 American

abbreviation

1. day.

2. December.

3. Democrat.

4. Democratic.

5. Physics. density.

6. Deus.

7. Deuteronomy.

8. Doctor.

9. dose.

10. Dutch.

d. 10 American

abbreviation

1. date.

2. daughter.

3. day.

4. deceased.

5. deep.

6. degree.

7. delete.

8. Physics. density.

9. depth.

10. deputy.

11. dialect.

12. dialectal.

13. diameter.

14. died.

15. dime.

16. dividend.

17. dollar; dollars.

18. dose.

19. drachma.

D 11 American Symbol.

1. the fourth in order or in a series.

2. (sometimes lowercase) (in some grading systems) a grade or mark, as in school or college, indicating the quality of a student's work as poor or barely passing.

3. (sometimes lowercase) a classification, rating, or the like, indicating poor quality.

4. Music.

   1. the second tone in the scale of C major, or the fourth tone in the relative minor scale, A minor.

   2. a string, key, or pipe tuned to this tone.

   3. a written or printed note representing this tone.

   4. (in the fixed system of solmization) the second tone of the scale of C major, called re.

   5. the tonality having D as the tonic note.

5. (sometimes lowercase) the Roman numeral for 500.

6. Chemistry. deuterium. Also 2H

7. Electricity.

   1. electric displacement.

   2. a battery size for 1.5 volt dry cells: diameter, 1.3 inches (3.3 centimeters); length, 2.4 inches (6 centimeters).

8. Biochemistry. aspartic acid.

9. a symbol for a shoe width size narrower than E and wider than C.

10. a proportional brassiere cup size larger than C.

'd 12 American

1. contraction of had:

   I was glad they'd gone.

2. contraction of did:

   Where'd they go?

3. contraction of should or would:

   He'd like to go. I'd like to remind you of your promise.

4. contraction of -ed:

   She OK'd the plan.

D. 1 British

abbreviation

1. politics Democrat(ic)

2. government Department

3. dinar(s)

4. Don (a Spanish title)

5. Duchess

6. Duke

7. (in the US and Canada) Doctor

"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 D 2 British

symbol

1. music

   1. a note having a frequency of 293.66 hertz ( D above middle C ) or this value multiplied or divided by any power of 2; the second note of the scale of C major

   2. a key, string, or pipe producing this note

   3. the major or minor key having this note as its tonic

2. chem deuterium

3. maths the first derivative of a function, as in D( x ³ + x ²) = 3 x ² + 2 x

4. physics

   1. dispersion

   2. electric displacement

5. aeronautics drag

6. 1. a semiskilled or unskilled manual worker, or a trainee or apprentice to a skilled worker

   2. ( as modifier ) See also occupation groupings

      D worker

7. 500 See Roman numerals

"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

abbreviation

1. Germany (international car registration)

2. 1. informal defence

      I'm playing D in the match this afternoon

   2. informal defensive play

"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 'd 3 British

contraction

1. would or had

   I'd

   you'd

"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 d 4 British

symbol

1. physics density or relative density

2. maths a small increment in a given variable or function: used to indicate a derivative of one variable with respect to another, as in d y /d x

3. chess See algebraic notation

"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 d 5 British / diː /

noun

1. the fourth letter and third consonant of the modern English alphabet

2. a speech sound represented by this letter, usually a voiced alveolar stop, as in dagger

3. the semicircle on a billiards table having a radius of 11 1/ 2 inches and its straight edge in the middle of the baulk line

"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 D 6 British

abbreviation

1. Deutsch: indicating the serial number in the catalogue (1951) of the musical compositions of Schubert made by Otto Deutsch (1883–1967)

"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 d. 7 British

abbreviation

1. (in animal pedigrees) dam

2. daughter

3. currency penny or pennies

4. diameter

5. died

6. dinar(s)

7. dollar(s)

8. drachma(s)

"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 d Scientific

1. Abbreviation of diameter

Etymology

Origin of d.1

From the Latin word dā

Origin of d.1

From the Latin word denāriī

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“He could be frustratingly closed off at times, and heartbreakingly candid at others. We’d sometimes write songs about each other and each other’s lives in oblique ways. But we seldom talked directly about feelings or deeply personal challenges. This was Greg, or at least one dimension of the complex kaleidoscope of who he was. Despite that, or maybe because of it, I loved him like a brother.”

From Los Angeles Times

"I'd say that tonight, our goal was really to loosen up a bit," said Fournier Beaudry.

From Barron's

Squali, of course, predicts the winners of the agentic shift are companies that control the search platforms such as Alphabet, Amazon, Meta, and OpenAI, which coincidently are also spending on the money on AI R&D.

From Barron's

Marantos was a dedicated reporter — she’d drive 60 miles to get an answer when no one was picking up the phone — but also devoted to her family.

From Los Angeles Times

We’d seen the famously star-studded house, or the casita, in both his San Juan residency and international tour run, which was duly brought back for the halftime show.

From Los Angeles Times

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.