Diacritic

A diacritic or diacritic(al) mark or diacritic(al) sign, in several writing systems, is a little sign added on a character, modifying slightly this character, in order to give any information about the pronunciation or, sometimes, in order to distinguish a word from another word. For instance: the character e becomes é, c becomes č, o becomes ø, s becomes ș, nh becomes n·h, ω becomes ώ, и becomes й, ر becomes دّ.

A letter with a diacritic is called a modified letter.

Concerned writing systems

Diacritics may occur in most writing systems.

• Some diacritics are unique to one writing system. For instance, the diacritic called shadda, indicating that a consonant is geminate (doubled), is typical of the Arabic alphabet: ر (d) with a shadda becomes دّ (dd) .
• Several diacritics may be shared by different but resembling writing systems. It is notably the case for the Roman, the Greek and the Cyrillic alphabets, which can share the acute accent (´) and the dieresis (¨).

Examples of diacritics

Roman alphabet

• accent
  • acute accent (´): á, ć, é, ǵ, í, ń, ó, ŕ, ś, ú, ẃ, ý, ź...
  • grave accent (`): à, è, ì, ò, ù, ẁ, ỳ...
  • double acute accent ( ˝ ): ő, ű...
  • circumflex accent ( ˆ ): â, ĉ, ê, ĝ, ĥ, î, ĵ, ô, ŝ, û, ŵ, ŷ, ẑ...
• breve ( ˘ ): ă, ĕ, ğ, ĭ, ŏ, ŭ...
• caron or haček ( ˇ ): č, ď (Ď), ě, ǧ, ň, ř, š, ť (Ť), ž...
• dieresis or umlaut (¨): ä, ë, ï, ö, ü, ÿ...
• macron ( ¯ ): ā, ē, ī, ō, ū, ȳ...
• cedilla ( ¸ ): ç, ş...
• comma (,): ģ (Ģ), ķ, ļ, ņ, ș, ț...
• ogonek or nosinė ( ˛ ): ą, ę, į, ǫ, ų...
• dot
  • overdot ( ̇ ): ċ, ė, ġ, ż...
  • underdot (  ̣ ): ạ, ḍ, ẹ, ḥ, ị, ọ, ṣ, ṭ, ụ, ẓ...
  • interpunct (·): ch·, g·, l·l, n·h, s·h...
• hook or dấu hỏi ( ̉ ): ả, ɓ, ƈ, ɗ, ẻ, ƒ, ɠ, ỉ, ƙ, ŋ, ỏ, ƥ, ƭ, ủ , ʋ, ⱳ, ỷ, ƴ, ȥ...
• horn or dấu móc ( ̛ ): ơ, ư...
• ring
  • ring above or kroužek ( ˚ ): å, ů...
  • ring below ( ˳ ): ḁ...
• tilde (  ̃ ): ã, ẽ, ĩ, ñ, õ, ũ...
• apostrophe (’): c’h...
• single opening quotation mark (‘): g‘, o‘...
• stroke (/): ð, đ, ħ, ł, ø...

Greek alphabet

• accent
  • acute accent (´): ά, έ, ή, ί, ό, ύ, ώ
  • grave accent (`): ὰ, ὲ, ὴ, ὶ, ὸ, ὺ, ὼ
  • perispomene, shaped like a Roman circumflex accent ( ˆ ) or like a Roman tilde (  ̃ ): ᾶ, ῆ, ῖ, ῦ, ῶ
• dieresis (¨): ϊ, ϋ
• iota subscript (ͺ): ᾳ, ῃ, ῳ
• breathing
  • smooth breathing or psili, resembling an apostrophe ( ᾿ ): ἀ, ἐ, ἠ, ἰ, ὀ, ὐ, ὠ, ῤ
  • rough breathing or dasia, resembling a right-oriented apostrophe ( ῾ ): ἁ, ἑ, ἡ, ἱ, ὁ, ὑ, ὡ, ῥ

Since 1982, diacritics have been simplified in modern Greek: only the acute accent (´) and the dieresis (¨) are still mandatory.

Status of modified letters

A letter with a diacritic is called a modified letter.

• In some languages, a modified letter (with a diacritic) is considered as a simple variant of the basic letter (without diacritic). For instance, in Portuguese, ç is nothing but a variant of the letter c.
• In other languages, a modified letter may be considered as an independent letter, having its own place in the alphabet and being totally distinct from the diacritic-less letter. For instance, in Turkish, ç is a different letter from c.

Quantity and frequency

The quantitity and the frequency of diacritics may differ.

• A few languages have no diacritics at all in the general use. It is notably the case of English and Malay (although some diacritics may be used optionally in some borrowings, as in English café or cafe, from French café).

• A lot of languages use diacritics, which frequency varies a lot according to the language in question.
  • For instance, diacritics are quite rare in Dutch, which uses sometimes ë (and rarely ä, ö, ï, ü), and in Italian, which uses sometimes ‑à, ‑è, ‑é, ‑ì, ‑ò, ‑ù at word ending.
  • On the opposite, other languages use a lot of different diacritics and may place them on nearly each word, as in Greek, Slovak or Czech, or even on each syllable, as in Vietnamese or Yoruba.

Diacritic affecting two characters

In general, a diacritic affects one character.

In a few languages, however, a diacritic is used to modify a group of letters, for instance:

• The dieresis in Spanish (gu → gü).
• The stroke in Maltese (gh → għ).
• The apostrophe in Breton (ch → c’h).
• The cedilla in Manx (ch → çh).
• The interpunct in Catalan (ll → l·l), in Occitan (nh → n·h, sh → s·h) or in Francoprovençal (ch → ch·).

Diacritics avoided on uppercases

A few languages tend to avoid certain diacritics attached to uppercase letters, under certain circumstances.

• When a word begins with an uppercase (the rest of the word being in lowercase):
  • In Greek, a diacritic is put above a lowercase but goes on the upper left side of an initial uppercase: ύφαλος (ýfalos) “underwater reef” becomes Ύφαλος.
  • Some users of French remove diacritics on initial uppercases, but this is nonstandard: école “school” becomes École or less correctly Ecole.
• In all-uppercase writings:
  • In Greek, diacritics are removed in all-uppercase writings: ύφαλος (ýfalos) “underwater reef” becomes ΥΦΑΛΟΣ, νερό (neró) “water” becomes ΝΕΡΟ. However, the dieresis (¨) remains in all cases: Ταΰγετος (Taÿ́getos) “Taygetus” becomes ΤΑΫΓΕΤΟΣ.
  • In Spanish and French, some users remove diacritics in all-uppercase writings, but this is nonstandard: Spanish águila “eagle” becomes ÁGUILA or less correctly AGUILA, French séquençage “sequencing” becomes SÉQUENÇAGE or less correctly SEQUENCAGE. However, the Spanish tilde (˜) remains in all cases: España “Spain” becomes ESPAÑA (never ESPANA*).
  • In Italian, the only usual diacritic is an acute or a grave accent at word ending. This accent may be replaced by an apostrophe on the upper right side of the last letter, but this is nonstandard: libertà “freedom” becomes LIBERTÀ or less correctly LIBERTA’.

Optional diacritics for pedagogical use

Some languages use certain diacritics only as a pedagogical help and remove them in general use. For instance, Russian only uses the acute accent (´) in learner-oriented publications, in order to show the place of the stress.