D
From Free net encyclopedia
- For other uses, see D (disambiguation).
The letter D is the fourth letter of the Latin alphabet. Its name in English is dee Template:IPA.
Contents |
History
| Egyptian hieroglyph "door" | Proto-Semitic D | Phoenician D | Etruscan D | Greek Delta |
|---|---|---|---|---|
| <hiero>O31</hiero> | Image:Proto-semiticD-01.pngImage:Proto-semiticD-02.png | Image:PhoenicianD-01.png | Image:EtruscanD-01.png | Image:GreekD-01.png |
The Semitic letter Dâlet probably developed from the logogram for a fish or a door. There are various Egyptian hieroglyphs that this might have inspired this. In Semitic, Ancient Greek and Latin, the letter was pronounced /d/; in the Etruscan alphabet the letter was superfluous, but still maintained (see letter B). Greek letter: Δ (capital) or δ (small) (Delta).
The minuscule (lower-case) form of D, consisting of a loop and a tall vertical stroke, developed by gradual variations on the majuscule (capital) form. In handwriting it was common to start the arc to the left of the vertical stroke, resulting in a serif at the top of the arc. This serif was extended while the rest of the letter was reduced, resulting in an angled stroke and loop. The angled stroke then developed into a vertical stroke.
Usage
The letter D generally takes the voiced alveolar plosive value, IPA Template:IPA in most languages that use the Roman alphabet, including English. Exceptions to this include Vietnamese, where it represents a voiced alveolar fricative (/z/) or a palatal approximant (/j/), similar to the English letters z or y (the letter đ is used for the sound similar to the English d). In Welsh d when doubled (dd) has the value Template:IPA, like English th in this.
Digraphs of D are rare in English, although other languages use DH or DD for a voiced dental fricative (some Celtic languages) or an aspirated voiced dental plosive (some Indo-Aryan languages), or use affricates DZ, DV, or DZH.
In Cantonese, the sound Template:IPA means a little bit, from the ancient use of the character 的 (in the phrase "兀的") in Chinese written language. Since 的 is no longer used in this way, Hong Kong residents invented a new character 啲 (which is not supported in many Chinese systems), or simply write D instead.
Codes for computing
{{Letter |NATO=Delta |Morse=–·· |Character=D4 |Braille=⠙ }} In Unicode the capital D is codepoint U+0044 and the lowercase d is U+0064.
The ASCII code for capital D is 68 and for lowercase d is 100; or in binary 01000100 and 01100100, correspondingly.
The EBCDIC code for capital D is 196 and for lowercase d is 132.
The numeric character references in HTML and XML are "D" and "d" for upper and lower case respectively.
Meanings
Science & Math
- In astronomy,
- D stands for destroyed/disappeared comet, as in D/1993 F2, Comet Shoemaker-Levy 9.
- In biochemistry, D is the symbol for aspartic acid.
- In chemistry, D is the symbol of deuterium, an isotope of hydrogen.
- In Earth Science the atmosphere of Earth, the D layer is part of the ionosphere.
- In economics, D stands for demand.
- In electronics, D is a standard size dry cell battery.
- In finance, D is the stock ticker symbol for Dominion Resources.
- In geometry, d is often a variable for the diameter of a circle.
- In mathematics,
- d is the symbol for the total differential operator (partial differentials use ∂).
- D is often used as a digit meaning thirteen in hexadecimal and other positional numeral systems with a radix of 14 or greater.
- Blackboard bold <math>\mathbb{D}</math> represents the unit disk in the complex plane, or the decimal fractions (see numbers).
- In metrology, d is the symbol for day (from the Latin dies; this is the only symbol for this unit acceptable for use with SI)
- In nutrition, D is a vitamin.
- In physics:
- In particle physics, d is the symbol of the deuteron.
- In molecular physics, D is the recommended symbol for: diffusion coefficient
- In molecular spectroscopy, d is the recommended symbol for: thickness, diameter, relative density (mechanics), lattice plane spacing (solid state physics), and degeneracy of vibrational mode.
- In solid state physics, D is the recommended symbol for: Debye-Waller factor.
- D is the recommended symbol for electric displacement.
- In the SI system, d, deci, is the SI prefix meaning one tenth, 10-1.
Others
- In American politics, D is often used as an abbreviation for a Democrat.
- Brassiere cup size D
- In British currency, d is an abbreviation (from the Latin denarius) for the pre-decimalization penny, worth 1/240th of a pound.
- In calendars, D is often an abbreviation for the month December.
- In computing,
- D is the name of various programming languages, most notably the D programming language by Walter Bright.
- D is a security division ("Minimal Protection") in the TCSEC.
- In driving a motor vehicle, D (drive) designates the forward cruising gears in an automatic transmission.
- In education, D is a barely passing grade.
- In finance, D is the New York Stock Exchange ticker symbol for the Richmond, Virginia company Dominion.
- In international licence plate codes, D stands for Germany.
- In music, D is a note.
- In print, D Magazine is a magazine for the city of Dallas, Texas.
- In Roman numerals, D denotes the number 500 (there are also separate Unicode characters for this number, 0x216E "Ⅾ" and 0x217E "ⅾ").
- In sports, D is often used as an abbreviation for defence.
- In video games, D is the title of a game released in the mid-1990s for PlayStation.
- D is also the name of a Japanese VK band.
- On the serial numbers of United States dollars, D identifies the Federal Reserve Bank of Cleveland.
See also
- Eth (Ð, ð)
- D with stroke (Đ, đ)
Template:AZsubnavals:D bs:D ca:D sn:D cs:D da:D de:D el:D es:D eo:D fr:D gl:D ko:D hr:D io:D id:D it:D he:D kw:D la:D hu:D nl:D ja:D no:D nn:D pt:D ro:D scn:D simple:D sl:D fi:D sv:D tl:D vi:D tr:D yo:D zh:D