Diacritic


A diacritic is a glyph added to a letter or to a basic glyph. The term derives from the Ancient Greek , from διακρίνω. The word diacritic is a noun, though it is sometimes used in an attributive sense, whereas diacritical is only an adjective. Some diacritics, such as the acute, grave, and circumflex , are often called accents. Diacritics may appear above or below a letter or in some other position such as within the letter or between two letters.
The main use of diacritics in Latin script is to change the sound-values of the letters to which they are added. Historically, English has used the diaeresis diacritic to indicate the correct pronunciation of ambiguous words, such as "coöperate", without which the letter sequence could be misinterpreted to be pronounced. Other examples are the acute and grave accents, which can indicate that a vowel is to be pronounced differently than is normal in that position, for example not reduced to /ə/ or silent as in the case of the two uses of the letter e in the noun résumé and the help sometimes provided in the pronunciation of some words such as doggèd, learnèd, blessèd, and especially words pronounced differently than normal in poetry.
Most other words with diacritics in English are borrowings from languages such as French to better preserve the spelling, such as the diaeresis on naïve and Noël, the acute from café, the circumflex in the word crêpe, and the cedille in façade. All these diacritics, however, are frequently omitted in writing, and English is the only major modern European language that does not have diacritics in common usage.
In Latin-script alphabets in other languages diacritics may distinguish between homonyms, such as the French là versus la, which are both pronounced. In Gaelic type, a dot over a consonant indicates lenition of the consonant in question. In other writing systems, diacritics may perform other functions. Vowel pointing systems, namely the Arabic harakat and the Hebrew niqqud systems, indicate vowels that are not conveyed by the basic alphabet. The Indic virama and the Arabic sukūn mark the absence of vowels. Cantillation marks indicate prosody. Other uses include the Early Cyrillic titlo stroke and the Hebrew gershayim, which, respectively, mark abbreviations or acronyms, and Greek diacritical marks, which showed that letters of the alphabet were being used as numerals. In Vietnamese and the Hanyu Pinyin official romanization system for Mandarin in China, diacritics are used to mark the tones of the syllables in which the marked vowels occur.
In orthography and collation, a letter modified by a diacritic may be treated either as a new, distinct letter or as a letter–diacritic combination. This varies from language to language and may vary from case to case within a language.
In some cases, letters are used as "in-line diacritics", with the same function as ancillary glyphs, in that they modify the sound of the letter preceding them, as in the case of the "h" in the English pronunciation of "sh" and "th". Such letter combinations are sometimes even collated as a single distinct letter. For example, the spelling sch was traditionally often treated as a separate letter in German. Words with that spelling were listed after all other words spelled with s in card catalogs in the Vienna public libraries, for example.

Types

Among the types of diacritic used in alphabets based on the Latin script are:
The tilde, dot, comma, titlo, apostrophe, bar, and colon are sometimes diacritical marks, but also have other uses.
Not all diacritics occur adjacent to the letter they modify. In the Wali language of Ghana, for example, an apostrophe indicates a change of vowel quality, but occurs at the beginning of the word, as in the dialects ’Bulengee and ’Dolimi. Because of vowel harmony, all vowels in a word are affected, so the scope of the diacritic is the entire word. In abugida scripts, like those used to write Hindi and Thai, diacritics indicate vowels, and may occur above, below, before, after, or around the consonant letter they modify.
The tittle on the letter or the letter, of the Latin alphabet originated as a diacritic to clearly distinguish from the minims of adjacent letters. It first appeared in the 11th century in the sequence ii, then spread to i adjacent to m, n, u, and finally to all lowercase is. The, originally a variant of i, inherited the tittle. The shape of the diacritic developed from initially resembling today's acute accent to a long flourish by the 15th century. With the advent of Roman type it was reduced to the round dot we have today.
Several languages of eastern Europe use diacritics on both consonants and vowels, whereas in western Europe digraphs are more often used to change consonant sounds. Most languages in Europe use diacritics on vowels, aside from English where there are typically none.

Diacritics specific to non-Latin alphabets

Arabic

  • hamza: indicates a glottal stop.
  • tanwīn symbols: Serve a grammatical role in Arabic. The sign ـً is most commonly written in combination with alif, e.g. ـًا.
  • shadda: Gemination of consonants.
  • waṣla: Comes most commonly at the beginning of a word. Indicates a type of hamza that is pronounced only when the letter is read at the beginning of the talk.
  • madda: A written replacement for a hamza that is followed by an alif, i.e.. Read as a glottal stop followed by a long, e.g. ءاداب، ءاية، قرءان، مرءاة are written out respectively as آداب، آية، قرآن، مرآة. This writing rule does not apply when the alif that follows a hamza is not a part of the stem of the word, e.g. نتوءات is not written out as نتوآت as the stem نتوء does not have an alif that follows its hamza.
  • superscript alif :
  • * fatḥa
  • * kasra
  • * ḍamma
  • * sukūn
  • The ḥarakāt or vowel points serve two purposes:
  • * They serve as a phonetic guide. They indicate the presence of short vowels or their absence.
  • * At the last letter of a word, the vowel point reflects the inflection case or conjugation mood.
  • ** For nouns, The ḍamma is for the nominative, fatḥa for the accusative, and kasra for the genitive.
  • ** For verbs, the ḍamma is for the imperfective, fatḥa for the perfective, and the sukūn is for verbs in the imperative or jussive moods.
  • Vowel points or tashkīl should not be confused with consonant points or Arabic diacritics – one, two or three dots written above or below a consonant to distinguish between letters of the same or similar form.