from The American Heritage® Dictionary of the English Language, 4th Edition
- The symbol for the isotope deuterium.
- The symbol for the Roman numeral 500.
- abbr. dative
- abbr. day
- abbr. Democrat
- abbr. down
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The fourth letter of the basic modern Latin alphabet.
- n. cardinal number five hundred (500).
- n. The fourth letter of the English alphabet, called dee and written in the Latin script.
- n. The ordinal number fourth, derived from this letter of the English alphabet, called dee and written in the Latin script.
- n. Deuterium, when it needs to be distinguished from ordinary hydrogen.
- n. Hexadecimal symbol for thirteen.
- n. A standard size of dry cell battery larger than C.
- n. Vehicle-distinguishing sign for Germany. (clarification of this Translingual definition is being sought)
- n. IUPAC one-letter abbreviation for aspartic acid.
- n. The differential operator in calculus and analysis.
- abbr. Defense.
- abbr. Democrat, especially preceding the constituent location.
- abbr. Divorced.
- abbr. Down (direction).
- abbr. Drive, the setting of an automatic transmission.
- abbr. Duodecimo, as adopted by the American Library Association.
- abbr. Dutch language.
- abbr. The City of Detroit.
- n. The semicircle on the baulk line, inside which the cue ball must be placed at a break-off.
- n. a grade awarded for a class, better than outright failure (which can be F or E depending on the institution) and worse than a C
From Etruscan 𐌃 (D), from Greek Δ (D, "Delta"), from Phoenician 𐤃 (D, "dalet"). (Wiktionary)
A simplification of Ð under the graphic influence of the letter D, from a standardization of Ɔ superposed on a ⋌ or ⊢, from the practice of circling each hundredth ⋌ (now Roman numeral V), the tally stick notch mark representing five. (Wiktionary)
Various abbreviations (Wiktionary)
From the shape of the upper case letter "D" (Wiktionary)
From the position (4) of the letter D in the English alphabet. (Wiktionary)