Diacritical

• Acute (as in á). In many languages, used to mark primary accent when it falls in a nonstandard place. In others, often used to change the quality of a vowel (by making it fronter, for example), or to make it longer. In a few languages, used to palatalise certain consonants.
• Grave (as in à). In many languages, used to change the quality of a vowel. Used in English poetry to indcate that a vowel which would normally be unstressed is being stressed for reasons of metre.
• Umlaut (as in ü). In many languages, used to apply the umlaut translation, which make back vowels (like `a', `o', `u') fronter.
• Diaeresis (as in ië). In many languages, used to indicate that two vowels are to be pronounced separately, rather than as a diphthong. In Dutch, for example, `ie' is pronounced /i:/, while `ië' is pronounced /i @/ (where @ is schwa). Diaeresis is written the same as umlaut, but is really a different diacritical.
• Double acute. Used in Hungarian to represent a long umlauted vowel.
• Macron. Used to indicate long vowels. In phonetic transcriptions of some languages (English, for example), indicates a change in vowel quality. For example, a-macron in English phonetics is really an umlauted a, while i-macron becomes a back-to-front diphthong. So-called `long vowels' in English are no longer long forms of the corresponding short vowels, thanks to the Great Vowel Shift.
• Ring (as in å). Used in some North Germanic (Scandinavian) languages to change the quality of the letter `a'. Technically, `å' is a completely different character, so `diacritical' is perhaps not a good word here.
• Circumflex (as in ê). Often used in French to indicate a vowel etymologically followed by an `s', but where the `s' had been dropped. For example, `bête', `hôte'. May also change vowel quality.
• Caron (inverted circumflex). Used in some Eastern European languages to indicate palatalisation of a consonant. Often called `hacek', from the Czech.
• Breve (concave-up curve). Used in phonetic descriptions to indicate short vowels.
• Tilde (ã). Used in many languages to indicate nasalised vowels. Used in some languages to indicate palatalised `n'.
• Cedilla (ç). Used in many languages to indicate that a vowel is palatalised or otherwise soft.
• Ogonek (like a backwards cedilla, on the lower-right of a character). Used in Polish on the letters `a' and `e' to change their quality and nasalise them.
• Dot above. Used over the letter `z' in Polish to hard-palatalise it (as opposed to the soft-palatalised z with acute)
• Slash (as in ø). Used to change the quality of the letter `o' in some Scandinavian languages. Like `å', `ø' is really a distinct character rather than a character with a diacritical.
• Bar. Used through the letter `l' in Polish to change its pronunciation from /l/ to /w/. L-bar (I can't remember the Polish for it at the moment) is considered a completely different letter.

More information regarding diacriticals in the Latin alphabet:

Regarding the umlaut: In some languages, the umlaut does not apply the umlaut transformation of making back vowels fronter, but instead has the effect of adding an e to the vowel in question. Sometimes this is represented as a ligature instead. See the nodes on ligatures, digraphs, and diphthongs.

Common or mathematical names for certain diacritical glyphs (see the Jargon File entry on ASCII for historical reasons behind these):

• acute: prime
• macron: bar
• circumflex: carat, hat, wedge
• caron: vee
• cedilla: comma, tail
• breve: cup
• concave-down curve: cap

How to type characters with diacritical marks:

• Copy and paste. There are plenty of places where you can find lists of special characters to copy from. For example, the HTML symbol reference node. Also, right here: ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿ
• Use a helper application. Each of the following will show you how to type special characters, and give you a place to type them into and copy and paste from:
  • On Mac OS: Apple Menu > Key Caps
  • On Mac OS X: Applications > Utilities > Key Caps
  • On Windows: Start Menu > Programs > Accessories > System Tools > Character Map
  • In any other operating system: please /msg me if you know
• Type them the way they were meant to be typed:
  Suppose you want to place the symbol (symbol) on the letter (letter).
  • On Mac OS:
    First: hold (option) while typing (symbol)
    Then: type (letter)
    Where (symbol) is:
    • acute: e
    • grave: `
    • circumflex: i
    • umlaut: u
    • tilde: n

    For example, if you want to type Á, first hold (option) while you type e, and then let go of (option) and type (shift)-a.

    Additionally, you can get å by typing (option)-a, ø by typing (option)-o, and ç by typing (option)-c. Get these in upper-case by holding (shift).

    Incidentally, Ÿ (capital Y with umlaut) is mapped to a dingbat on some Mac OS standard fonts such as Geneva.

  • In Microsoft Word for Windows: (This is typically easier to remember than the Mac OS paradigm, but more physically difficult to execute.)
    First: hold (control) while typing (symbol)
    Then: type (letter)
    Where (symbol) is:
    • acute: '
    • grave: `
    • circumflex: ^
    • umlaut: :
    • tilde: ~
    • slash: /
    • cadilla: ,

    For example, if you want to type Á, first hold (control) while you type ', then let go of control and type (shift)-a.

    Note that this only works for characters in Microsoft ASCII, even though Microsoft Word is capable of typesetting fonts that contain more extensive sets of glyphs.

  • On Windows or Unix in general:

    Hold (alt) while typing the decimal number corresponding to the ASCII character you want, then release (alt). It may help you to know that, in Microsoft ASCII, modified roman characters begin at 192, and lower-case ones are generally 32 greater than their upper-case equivalents, similar to letters in standard ASCII.

    For example, to get Á on Windows, you would hold (alt), type 192, and then release (alt).

  • In TeX:
    \(symbol){(letter)}
    Where (symbol) is:
    • acute: '
    • grave: `
    • double acute: H
    • circumflex: ^
    • caron: v
    • umlaut: "
    • tilde: ~
    • macron: =
    • bar under: b
    • dot over: .
    • dot under: d
    • breve: u
    • cap: t
    • cedilla: c

    For example, if you wanted to get Á, you would enter \'{A}

    You can also enter Æ as \AE, Œ as \OE, Å as \AA, Ø as \O, and &Lslash; as \L. Each of these has the obvious lower-case equivalent.

  • In HTML (see the HTML symbol reference for a complete list): &(letter)(symbol);
    Where (symbol) is:
    • acute: acute
    • grave: grave
    • circumflex: circ
    • tilde: tilde
    • umlaut: uml
    • ring: ring
    • ligature: lig
    • cedilla: cedil
    • slash: slash

    For example, if you wanted to get Á, you would enter Á

Diacritical marks in other languages:

Diacritical marks in the Greek alphabet (breathing marks): Concave-left and concave-right marks above a vowel or a ρ when it begins a word. The concave-right one means to breathe an h sound before the letter. See the node on them.

Diacritical marks in the Japanese phonetic alphabets, hiragana and katakana:

• Dakuten (two little lines in upper right of glyph): Makes an unvoiced consonant voiced. That is, transforms k to g, s to z, t to d, and h to b.
• Handakuten (little circle in upper right of glyph): Makes an unvoiced consonant semivoiced. That is, transforms h to p

(Thanks to Juuichiketajin for the names of the Japanese diacritical marks.)

Di`a*crit"ic (?), Di`a*crit"ic*al (?), a. [Gr. , fr. to separate, distinguish; through + to separate. See Critic.]

That separates or distinguishes; -- applied to points or marks used to distinguish letters of similar form, or different sounds of the same letter, as, a, &acr;, a, &omac;, &ocr;, etc.

Sir W. Jones.

A glance at this typography will reveal great difficulties, which diacritical marks necessarily throw in the way of both printer and writer. A. J. Ellis.

© Webster 1913.