the fourth letter of the English alphabet, a consonant.

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

something having the shape of a D.

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

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

de (used in French names as an elided form of de )

Charles Louis d'Albert.

di (used in Italian names as an elided form of di )

Gabriele d'Annunzio.

contraction of had

I was glad they'd gone.

contraction of did

Where'd they go?

contraction of should or would

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

contraction of - ed

She OK'd the plan.

Electricity . debye.

deep.

depth.

Optics . diopter.

divorced.

Dutch.

the fourth in order or in a series.

( 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.

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

Music .

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

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

a written or printed note representing this tone.

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

the tonality having D as the tonic note.

( sometimes lowercase ) the Roman numeral for 500. Compare Roman numerals .

Chemistry . deuterium.

Electricity .

electric displacement.

a battery size for 1.5 volt dry cells

diameter, 1.3 in. (3.3 cm); length, 2.4 in. (6 cm).

Biochemistry . aspartic acid.

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

a proportional brassiere cup size larger than C.

day.

December.

Democrat.

Democratic.

Physics . density.

Deus.

Deuteronomy.

Doctor.

dose.

Dutch.

(in prescriptions) give.