The grave accent ( ` ) is a diacritical mark used in written Breton, Catalan, Dutch, French, Greek (until 1982; see polytonic orthography), Italian, Norwegian, Occitan, Portuguese, Scottish Gaelic, Vietnamese, Welsh, and other languages.
The word grave is derived from the Latin gravis (heavy). In English, the word is sometimes pronounced [ˈɡrɑːv] grav, not like the word grave meaning "serious" or "tomb", which is pronounced greiv. It comes from French, where it is pronounced similarly; accent grave is pronounced [aksɑ̃ ɡʁav].
The grave accent was first used in the polytonic orthography of Ancient Greek, where it occurred only on the last syllable of a word, in cases where the normal high pitch (indicated by an acute accent) was lowered because of a following word in the same sentence. Since Modern Greek has a stress accent instead of a pitch accent, this diacritic has been replaced with an acute accent mark in the modern monotonic orthography.
Phonetically, the grave accent originally marked a heavier and louder tone, as opposed to the acute accent that marked a sharp pitch. Visually as well, it is the exact opposite of the acute accent, being its mirror image. In nearly all fonts, the accent mark is similar to a top-heavy triangle with its sharp point extending rightwards.
The grave accent marks the stressed vowel of a word in Catalan and Italian. Some examples from Italian are città "city", morì "[he/she] died", virtù "virtue", Mosè "Moses", portò "[he/she] brought, carried". Especially with capital letters, or when using a keyboard without accented letters, an apostrophe is sometimes used instead of it in Italian, thus E’ instead of È "[he/she/it] is", though this is considered (at least) inelegant and inaccurate (though the phrase un po’ meaning "a little" is never spelt un pò, because it's a truncated version of un poco).
In Italian there are pairs of words, one accented 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 Norwegian (both Bokmål and Nynorsk), the grave accent is used to separate words which would otherwise be identical, for instance "og" (and) and "òg" (too). Popular usage, possibly because Norwegian rarely uses diacritics, often leads to a grave accent being used in place of an acute accent.
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:
Catalan uses the accent on three letters (a, e, and o).
French uses the accent on three letters (a, e, and u), but only with e does it serve to indicate a pronunciation change. For example, the accent mark in lève [lεv], indicates that it is not pronounced as a schwa, like in lever [ləve].
The grave accent is used to distinguish homophones in several languages:
Catalan, where it distinguishes, for example, ma ("my") from mà ("hand").
French. The grave accent on the letters a and u has no effect on pronunciation and only serves to distinguish homonyms that are otherwise spelled the same. It distinguishes the preposition à ("to") from the verb a (the third-person singular present tense of avoir), as well as the adverb là ("there") and the feminine definite article la; it is also used in the word déjà and the phrase çà et là ("hither and thither"; without the accent, it would literally mean "it and the"). It is used on the letter u only to distinguish où ("where") and ou ("or"). È is rarely used to distinguish homonyms, except in dès/des ("since/some") and ès/es ("in/are").
Italian, where it distinguishes for example the conjunction e "and" from the verb è ("he/she/it is"), or the feminine article la from the adverb là ("there").
Norwegian, where it differentiates between certain words, such as og ("and") and òg ("also").
In Welsh, the accent is used to denote a short vowel sound in a word which would otherwise be pronounced with a long vowel sound, for example mẁg "mug" versus mwg "smoke".
In Scottish Gaelic, it denotes a long vowel (the use of acute accents is seen in older texts, but is no longer allowed according to the new orthographical conventions).
In some tonal languages such as Vietnamese and Mandarin Chinese (when written in Hanyu Pinyin or Zhuyin Fuhao), the grave accent is used to indicate a falling tone. The alternative to the grave accent in Mandarin is number 4 after the syllable: pà = pa4.
In African languages, the grave accent is often used to indicate a low tone, e.g. Nobiin jàkkàr 'fish-hook', Yoruba àgbọ̀n 'chin', Hausa màcè 'woman'.
In Portuguese, the grave accent indicates the contraction of two consecutive vowels in adjacent words (crasis). For example, instead of a (at) aquela (that) hora (hour), one says and writes àquela hora "at that hour".
In Hawaiian, the grave accent is used to place a break, or glottal stop, in a word. For more on the Hawaiian use of the grave accent, see the ‘okina.
Use in English
The grave accent is most often used in English in poetry and song lyrics. It indicates that a vowel usually silent is to be pronounced, in order to fit the rhythm or meter. Most often, it is applied to a word ending with -ed. For instance, the word looked is usually pronounced /ˈlʊkt/ as a single syllable, with the e silent; when written as lookèd, the e is pronounced: /ˈlʊk.ɨd/ look-ed). It can also be used in this capacity to distinguish certain pairs of identically spelled words like the past tense of learn, learned /ˈlɜrnd/, from the adjective learnèd /ˈlɜrn.ɨd/.
Italics, with appropriate accents, are generally applied to foreign terms that are uncommonly used in or have not been assimilated into English: for example, vis-à-vis, pièce de résistance and crème brûlée
The ISO-8859-1 character encoding includes the letters à, è, ì, ò, ù, and their respective capital forms. Dozens more letters with the grave accent are available in Unicode.
In the ASCII character set the grave accent is encoded as character 96, hex 60. Unicode also provides the grave accent as a combining character, encoded as 768, hex 300. 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 many computer keyboards, the grave accent occupies a key by itself, and is meant to be combined with vowels as a multi-key combination or as a dead key to modify the following letter. However, programmers have used the key by itself for a number of tasks.
On a Mac, to get a character, such as à, the user must type Option-` and then the vowel. For example, to make à, the user must type Option-` and then 'a', and to make À, the user must type Option-` and then Shift-a.
On a system running the X Window System, to get a character such as à, the user should press compose, ` then the vowel. The compose key on modern keyboards is usually mapped to a Windows key or shift+AltGR.
On a US and UK QWERTY keyboard, the grave accent key is placed in the top left corner. In many PC based computer games the key is used to open the console window, allowing the user to execute commands via a CLI.
When using TeX to typeset text, the grave accent on its own is used in lieu of a dedicated open-quote key. For example,
` becomes a single opening quote (‘) and
`` becomes a double opening quote (“). Compared to algorithmic ‘smart quotes’ available in modern word processors, this method has the advantage of it becoming completely unambiguous (consider "
the ’60s" or the archaic "
’twas" – most modern word processors would incorrectly render these as "
the ‘60s" and "
‘twas", respectively). The primary disadvantage is that it requires the user to adjust to this style.
Many of the Unix shells and the programming languages Mythryl, Perl, Ruby and PHP use pairs of this character—known as backquote or backtick—to indicate substitution of the standard output from one command into a line of text defining another command. For example, <tt>echo `date`</tt> might execute <tt>echo Sat Mar 1 09:43:00 GMT 2008</tt> and print <tt>Sat Mar 1 09:43:00 GMT 2008</tt>.
In Lisp macro systems, the backquote character (called quasiquote in Scheme) introduces a quoted expression in which comma-substitution may occur. It is identical to the plain quote, except that symbols prefixed with a comma will be replaced with those symbols' values as variables. This is roughly analogous to the Unix shell's variable interpolation with <CODE>$</CODE> inside double quotes.
In MySQL, it is used in queries as a table and database classifier.
In Pico, the backquote is used to indicate comments in the programming language.
Microsoft Windows PowerShell uses the backquote as the escape character. For example, a newline character is denoted
`n. Most commonly used programming languages use a backslash as the escape character (e.g.
\n) but because Windows allows the backslash as a path separator, it would have been impractical for PowerShell to use backslash for a different purpose. To get the
` character itself, use two backticks. For example the nullable boolean of .NET is specified in PowerShell as
In the Python programming language, "backticks" are used as a synonym for the
repr() function, which converts its argument to a string suitable for a programmer to view. However, this feature has been removed in Python 3.0. Backticks are also used extensively in the reStructuredText plain text markup language (implemented in the Python docutils package).
In Verilog the grave accent is used to define constants (e.g. after the line
`define NUM 100,
`NUM can be used as a synonym for
100) whereas the apostrophe is used in specifying sized constants (for example,
5'd10 is a 5-bit constant with the value 10). Accidental use of an apostrophe instead of a grave accent and vice versa is a source of frequent beginner mistakes in the language.
In Unlambda, the backquote character denotes function application. (Wikipedia)