Grave accent

The grave accent ( ` ) ([1][2] or [1][2]) is a diacritical mark used to varying degrees in English, French, Dutch, Portuguese, Italian and many other western European languages. It is also used in other languages using the Latin alphabet, such as Mohawk and Yoruba, and with non-Latin writing systems such as the Greek and Cyrillic alphabets and the Bopomofo or Zhuyin Fuhao semi-syllabary. It has no single meaning, but can indicate pitch, stress, or other features.

The grave accent first appeared in the polytonic orthography of Ancient Greek to mark a lower pitch than the high pitch of the acute accent. In modern practice, it replaces an acute accent in the last syllable of a word when that word is followed immediately by another word. The grave and circumflex have been replaced with an acute accent in the modern monotonic orthography.

The accent mark was called βαρεῖα, the feminine form of the adjective βαρύς (barús), meaning "heavy" or "low in pitch". This was calqued (loan-translated) into Latin as gravis, which then became the English word grave.

The grave accent marks the stressed vowels of words in Maltese, Catalan, and Italian.

A general rule in Italian is that words that end with stressed -a, -i or -u must be marked with a grave accent. Words that end with stressed -e or -o may bear either an acute accent or a grave accent, depending on whether the final e or o sound is closed or open, respectively. Some examples of words with a final grave accent are città ("city"), così ("so/then/thus"), più ("more"/"plus"), Mosè ("Moses"), and portò ("[he/she/it] brought/carried"). Typists who use a keyboard without accented characters and are unfamiliar with input methods for typing accented letters sometimes use a separate grave accent or even an apostrophe instead of the proper accent character. This is nonstandard but is especially common when typing capital letters: *E` or *E’ instead of È ("[he/she/it] is"). Other mistakes arise from the misunderstanding of truncated and elided words: the phrase un po’ ("a little"), which is the truncated version of un poco, may be mistakenly spelled as *un pò. Italian has word pairs where one has an accent marked and the other not, with different pronunciation and meaning—such as pero ("pear tree") and però ("but"), and Papa ("Pope") and papà ("dad"); the last example is also valid for Catalan.

In Bulgarian, the grave accent sometimes appears on the vowels а, о, у, е, и, and ъ to mark stress. It most commonly appears in books for children or foreigners, and dictionaries—or to distinguish between near-homophones: па̀ра (pàra, "steam/vapour") and пара̀ (parà, "cent/penny, money"), въ̀лна (vằlna, "wool") and вълна̀ (vǎlnà, "wave").

In Macedonian the stress mark is orthographically required to distinguish homographs (see Disambiguation) and is put mostly on the vowels е and и. Then, it forces the stress on the accented word-syllable instead of having a different syllable in the stress group getting accented. In turn, it changes the pronunciation and the whole meaning of the group.

Ukrainian, Rusyn, Belarusian, and Russian used a similar system until the first half of the 20th century. Now the main stress is preferably marked with an acute, and the role of the grave is limited to marking secondary stress in compound words (in dictionaries and linguistic literature).

In Croatian, Serbian, and Slovene, the stressed syllable can be short or long and have a rising or falling tone. They use (in dictionaries, orthography, and grammar books, for example) four different stress marks (grave, acute, double grave, and inverted breve) on the letters a, e, i, o, r, and u: à è ì ò r̀ ù. The system is identical both in Latin and Cyrillic scripts. Unicode forgot to encode R-grave when encoding the letters with stress marks.

In modern Church Slavonic, there are three stress marks (acute, grave, and circumflex), which formerly represented different types of pitch accent. There is no longer any phonetic distinction between them, only an orthographical one. The grave is typically used when the stressed vowel is the last letter of a multiletter word.

In Ligurian, the grave accent marks the accented short vowel of a word in à (sound [a]), è (sound [ɛ]), ì (sound [i]) and ù (sound [y]). For ò, it indicates the short sound of [o], but may not be the stressed vowel of the word.[citation needed]

The grave accent marks the height or openness of the vowels e and o, indicating that they are pronounced open: è [ɛ] (as opposed to é [e]); ò [ɔ] (as opposed to ó [o]), in several Romance languages:

In several languages, the grave accent distinguishes both homophones and words that otherwise would be homographs:

In Welsh, the accent denotes a short vowel sound in a word that would otherwise be pronounced with a long vowel sound: mẁg [mʊɡ] "mug" versus mwg [muːɡ] "smoke".

In Scottish Gaelic, it denotes a long vowel, such as cùis [kʰuːʃ] ("subject"), compared with cuir [kʰuɾʲ] ("put"). The use of acute accents to denote the rarer close long vowels, leaving the grave accents for the open long ones, is seen in older texts, but it is no longer allowed according to the new orthographical conventions.

In some tonal languages such as Vietnamese, and Mandarin Chinese (when it is written in Hanyu Pinyin or Zhuyin Fuhao), the grave accent indicates a falling tone. The alternative to the grave accent in Mandarin is the numeral 4 after the syllable: pà = pa4.

In African languages and in International Phonetic Alphabet, the grave accent often indicates a low tone: Nobiin jàkkàr ("fish-hook"), Yoruba àgbọ̀n ("chin"), Hausa màcè ("woman").

In Emilian-Romagnol, a grave accent placed over e or o denotes both length and openness. In Emilian è and ò represent [ɛː] and [ɔː], while in Romagnol they represent [ɛ] and [ɔ].

In Portuguese, the grave accent indicates the contraction of two consecutive vowels in adjacent words (crasis). For example, instead of a aquela hora ("at that hour"), one says and writes àquela hora.

In Hawaiian, the grave accent is not placed over another character but is sometimes encountered as a typographically easier substitute for the ʻokina: Hawai`i instead of Hawaiʻi.

The grave accent, though rare in English words, sometimes appears in poetry and song lyrics to indicate that a usually-silent vowel is pronounced to fit the rhythm or meter. Most often, it is applied to a word that ends with -ed. For instance, the word looked is usually pronounced as a single syllable, with the e silent; when written as lookèd, the e is pronounced: look-ed). In this capacity, it can also distinguish certain pairs of identically spelled words like the past tense of learn, learned , from the adjective learnèd (for example, "a very learnèd man").

A grave accent can also occur in a foreign (usually French) term which has not been anglicised: for example, vis-à-vis, pièce de résistance or crème brûlée. It also may occur in an English name, often as an affectation, as for example in the case of Albert Ketèlbey.

The layout of some European PC keyboards combined with problematic keyboard driver semantics causes many users to use a grave accent or an acute accent instead of an apostrophe when typing in English (e.g. typing Brian`s Theater or Brian´s Theater instead of Brian's Theater).[3]

Additionally ASCII grave accent character (U+0060 ` GRAVE ACCENT) was often used as surrogate of opening single quote, together with ASCII typewriter apostrophe ( U+0027 ' APOSTROPHE) used as closing single quote; double quotes were sometimes substituted by two consecutive grave accents and two consecutive typewriter apostrophes (``…''). Although Unicode now provides separate characters for single and double quotes, such style is sometimes used even nowadays; examples are: output generated by some UNIX console programs, rendering of man pages within some environments, technical documentation written long ago or written in old-school manner. However, as time goes on, such style is used less and less, and even institutions that traditionally were using that style are now abandoning it.[4][5]

The Unicode standard makes dozens of letters with a grave accent available as precomposed characters. The older ISO-8859-1 character encoding only includes the letters à, è, ì, ò, ù, and their respective capital forms. In the much older, limited 7-bit ASCII character set, the grave accent is encoded as character 96 (hex 60). Outside the US, character 96 is often replaced by accented letters. In the French ISO 646 standard, the character at this position is µ. Many older UK computers, such as the ZX Spectrum and BBC Micro, have the £ symbol as character 96, though the British ISO 646 variant ultimately placed this symbol at position 35 instead.

On British and American keyboards, the grave accent is a key by itself. Due to the character's presence in ASCII, this is primarily used to actually type that character, though some layouts (such as US International or UK extended) may use it as a dead key to modify the following letter. (With these layouts, to get a character such as à, the user can type ` and then the vowel. For example, to make à, the user can type ` and then a). In territories where the diacritic is used routinely, the precomposed characters are provided as standard on national keyboards.

On a Mac, to get a character such as à, the user can type ⌥ Option+` and then the vowel. For example, to make à, the user can type ⌥ Option+` and then a, and to make À, the user can type ⌥ Option+` and then ⇧ Shift+a. In iOS and most Android keyboards, combined characters with the grave accent are accessed by holding a finger on the vowel, which opens a menu for accents. For example, to make à, the user can tap and hold a and then tap or slide to à. Mac versions of OS X Mountain Lion (10.8) or newer share similar functionality to iOS; by pressing and holding a vowel key to open an accent menu, the user may click on the grave accented character or type the corresponding number key displayed.

On a system running the X Window System, to get a character such as à, the user should press Compose followed by `, then the vowel. The compose key on modern keyboards is usually mapped to a ⊞ Win key or ⇧ Shift+Alt Gr.[6]

In many PC-based computer games in the US and UK, the ` key (on US English and UK keyboards) is used to open the console so the user can execute script commands via its CLI.[citation needed] This is true for games such as Factorio, Battlefield 3, Half-Life, Halo CE, Quake, Half-Life 2, Blockland, Soldier of Fortune II: Double Helix, Unreal, Counter-Strike, Crysis, Morrowind, Oblivion, Skyrim,[7] Fallout: New Vegas, Fallout 3, Fallout 4, RuneScape, and games based on the Quake engine or Source engine.[citation needed]

Programmers use the grave accent symbol as a separate character (i.e., not combined with any letter) for a number of tasks. In this role, it is known as a backquote, or backtick.

Many of the Unix shells and the programming languages Perl, PHP, and Ruby use pairs of this character to indicate command substitution, that is, substitution of the standard output from one command into a line of text defining another command. For example, using $ as the symbol representing a terminal prompt, the code line:

This is also the format the Markdown formatter uses to indicate code.[8] Some variations of Markdown support "fenced code blocks" that span multiple lines of code, starting (and ending) with three backticks in a row (```).[9]

Various programming and scripting languages use the backquote character:

The use of backticks for command substitution is now largely deprecated in favor of the notation $(...), so that one of the examples above would be re-written:

The latter syntax allows easier multiple nesting than with backquotes such as, for example:

The backquote character is valid at the beginning of or within a variable, structure, procedure or function name.
Surrounding an identifier with double backquotes allows the use of identifiers that would not otherwise be allowed, such as keywords, or identifiers containing punctuation or spaces.
A backquote together with an apostrophe quotes strings (to suppress or defer macro expansion).
A backquote in queries is a delimiter for column, table, and database identifiers.