| D | Day | |
| D | Date | |
| D | Data | |
|
| D | Daily | |
| D | 500 (Roman numeral) | |
| D | Digital | |
| D | Drive | |
| D | Display | |
| D | Distance | |
| D | Director (Drone Control; US military aircraft designation; as in D-21) | |
| D | Dead | |
| D | Drive (automatic transmissions) | |
| D | Degree | |
| D | Dutch | |
| D | Division | |
| D | Daughter | |
|
| D | Deutschland (Germany) (International Auto Identification) | |
| D | Draw (a tie; sports) | |
| D | Dallas, TX, USA | |
| D | Discuss | |
| D | Depth | |
| D | Device | |
| D | Distance Vision | |
| D | Delta | |
| D | Denver, Colorado (mint mark) | |
| D | Diablo (roleplaying game) | |
| D | Defense | |
| D | Dedicated (Channel) | |
| D | Diesel | |
| D | Drum | |
| D | Battery Size | |
| D | Delay | |
| D | Dublin (car registration identification) | |
| D | Diversity | |
| D | Duty Factor | |
| D | Depot | |
| D | Departure | |
| D | Penny (old British penny) | |
| D | Diamonds (playing cards) | |
| D | Demonstration | |
| D | Duke (British title of nobility) | |
| D | Diameter | |
| D | Density | |
| D | Dragon (Yu-Gi-Oh!) | |
| D | Datum | |
| D | Desperados (game) | |
| D | Drain (transistor; electronics) | |
| D | Dimensional | |
| D | Daytime (broadcasting operating schedule) | |
| D | Digit | |
| D | Doctrine | |
| D | Deed (real estate) | |
| D | Deaf (member of the Deaf Community who shares a sense of Deaf Culture) | |
| D | Drag Force (aerodynamic equations) | |
| D | Diarrhea | |
| D | Düsseldorf (Germany) | |
| D | Differential | |
| D | Directing | |
| D | Derivative | |
| D | Deceased | |
| D | Dummy | |
| D | Detective (NSW, Australia) | |
| D | Detective (police) | |
| d | Deaf (person who can not hear but is not part of the Deaf Community) | |
| D | Democrat | |
| D | Dependency | |
| D | Diners Club (credit card) | |
| D | Decimal | |
| D | Disconnect | |
| D | Doubtful (player's likelihood of participating) | |
| D | Dinar | |
| D | Diode | |
| D | Absorbed Dose | |
| D | Dominion Resources Inc (stock symbol) | |
| D | Diffusion Coefficient | |
| D | Tenacious D (band) | |
| D | Denominator | |
| D | Dorsal | |
| D | Tunisian Dinar (unit of currency) | |
| D | Dielectric | |
| D | Defenseman (hockey) | |
| D | Deci- (metric prefix, 1/10) | |
| D | Diastolic (blood pressure) | |
| D | Decedent (IRB) | |
| D | Decrement | |
| D | Aspartic Acid (amino acid) | |
| D | Deuterium | |
| D | Dahlonega, Georgia (mint mark, 1838-61) | |
| D | Diopter (unit of optical power) | |
| D | Diamox (medicine) | |
| D | Diaphragmatic | |
| D | Delete(d) (action code) | |
| D | Denarius (Roman Coin) | |
| D | Debye (unit of dipole moment) | |
| D | Calciferol (vitamin) | |
| D | Derated | |
| D | Degaussing | |
| D | Doubleword | |
| D | Die/Dice (role play reference) | |
| D | Dextrorotary (clockwise optical rotaton) | |
| D | Drift distance | |
| D | Pneumatic Post (Scott Catalogue prefix; philately) | |
| D | Below Average grade | |
| D | Documentary Division | |
| D | D Sub-Shell (third outer subshell of an electron shell) | |
| D | Denarius/Penny (nail size) | |
| D | District spare (Stores 100 code) | |
| D | Federal Reserve Bank of Cleveland, Ohio (designates original point of circulation of a dollar bill) | |
| D | Cohen's Measure of Effect Size (statistics; usually expressed as italic d) | |
| D | Deutschverzeichnis (Works of Schubert by Otto Erich Deutsch) | |
| D | Undenominated United States Stamp (22 cents, introduced 17 Nov 1985) | |
| D | Total Outside Dose (radiation) | |
| D | Total Drift, Data (US DoD) | |
| D | Radioplane Company (manufacturer's symbol) | |
| d | Surface Drift (US DoD) | |