Dash


The dash is a punctuation mark that is similar in appearance to the hyphen and minus sign but differs from these symbols in length and, in some fonts, height [|above] the baseline. The most common versions of the dash are the endash, longer than the hyphen; the emdash, longer than the en dash; and the horizontalbar, whose length varies across typefaces but tends to be between those of the en and em dashes.
Historically, the names of endash and emdash came from the width of an uppercase and uppercase, respectively, in commonly used fonts.

Types of dash

Usage varies both within English and in other languages, but the usual convention in printed English text is as follows:
There are several forms of dash, of which the most common are:
glyphUnicode code pointUnicode nameHTML character entity referenceHTML/XML numeric character referencesTeXAlt code macOS key combinationCompose keyvim digraphMicrosoft Word key combinationGTK+ apps
figure dash‒U+2012‒
‒		+
en dash–U+2013––
–		--
em dash—U+2014——
—		---
horizontal bar―U+2015――
―
swung dash⁓U+2053⁓
⁓		$\sim$

Less common are the two-em dash and three-em dash, both added to Unicode with version 6.1 as U+2E3A and U+2E3B.

Figure dash

The figure dash has the same width as a numerical digit; most fonts have digits of equal width. It is used within numbers, especially in columns, for maintaining alignment. Its meaning is the same as a hyphen, as represented by hyphen-minus. In contrast, the en dash is generally used for a range of values. The minus sign glyph is generally set a little higher.
When the figure dash is unavailable, a hyphen-minus is often used instead. In Unicode, the figure dash is . HTML provides no character entity for it; it can be represented by the numeric character reference ‒ or ‒.
In TeX, the standard fonts have no figure dash; however, the digits normally all have the same width as the en dash, so an en dash can be substituted. In XeLaTeX, one can use \char"2012. The Linux Libertine font also has the figure dash glyph.

En dash

The en dash, en rule, or nut dash is traditionally half the width of an em dash.
In modern fonts, the length of the en dash is not standardized, and the en dash is often more than half the width of the em dash. The widths of en and em dashes have also been specified as being equal to those of the upper-case letters N and M, respectively,
and at other times to the widths of the lower-case letters.

Usage

The three main uses of the en dash are to connect symmetric items, such as the two ends of a range or two competitors or alternatives, as a substitute for a hyphen in a compound when one of the connected items is more complex than a single word, and as an at sentence level, substituting for a pair of commas, parentheses, or to indicate a rhetorical pause. It is sometimes held that, when used as an interruptor, the en dash should be "open" – spaced on both sides – in contrast to the em dash, which is closed.

Ranges of values

The en dash is commonly used to indicate a closed range of values – a range with clearly defined and finite upper and lower boundaries – roughly signifying what might otherwise be communicated by the word "through". This may include ranges such as those between dates, times, or numbers. Various style guides restrict this range indication style to only parenthetical or tabular matter, requiring "to" or "through" in running text. Preference for hyphen vs. en dash in ranges varies. For example, the APA style uses an en dash in ranges, but the AMA style uses a hyphen:
En dash range style Hyphen range style Running text spell-out
June–July 1967JuneJuly 1967June and July 1967
1:15–2:15 p.m.1:152:15 p.m.1:15 to 2:15 p.m.
For ages 3–5For ages 35For ages 3 through 5
pp. 38–55pp. 3855pages 38 to 55
President Jimmy Carter President Jimmy Carter President Jimmy Carter, in office from 1977 to 1981

Some style guides recommend that, when a number range might be misconstrued as subtraction, the word "to" should be used instead of an en dash. For example, "a voltage of 50 V to 100 V" is preferable to using "a voltage of 50–100 V". Relatedly, in ranges that include negative numbers, "to" is used to avoid ambiguity or awkwardness. It is also considered poor style to use the en dash in place of the words "to" or "and" in phrases that follow the forms from X to Y and between X and Y.

Relationships and connections

The en dash is used to contrast values or illustrate a relationship between two things. Examples of this usage include:
A distinction is often made between "simple" attributive compounds and other subtypes ; at least one authority considers name pairs, where the paired elements carry equal weight, as in the Taft–Hartley Act to be "simple", while others consider an en dash appropriate in instances such as these to represent the parallel relationship, as in the McCain–Feingold bill or Bose–Einstein statistics. When an act of the U. S. Congress is named using the surnames of the senator and representative who sponsored it, the hyphen-minus is used in the short title; thus the short title of Public Law 111–203 is "The Dodd-Frank Wall Street Reform and Consumer Protection Act", with a hyphen-minus rather than an en dash between "Dodd" and "Frank". However, there is a difference between something named for a parallel/coordinate relationship between two people and something named for a single person who had a compound surname, which may be written with a hyphen or a space but not an en dash. Copyeditors use dictionaries to confirm the eponymity for specific terms, given that no one can know them all offhand.
Preference for an en dash instead of a hyphen in these coordinate/relationship/connection types of terms is a matter of style, not inherent orthographic "correctness"; both are equally "correct", and each is the preferred style in some style guides. For example, the American Heritage Dictionary of the English Language, the AMA Manual of Style, and Dorland's medical reference works use hyphens, not en dashes, in coordinate terms, in eponyms, and so on.

Attributive compounds

In English, the en dash is usually used instead of a hyphen in compound attributives in which one or both elements is itself a compound, especially when the compound element is an, meaning it is not itself hyphenated. This manner of usage may include such examples as:
The disambiguating value of the en dash in these patterns was illustrated by Strunk and White in The Elements of Style with the following example: When Chattanooga News and Chattanooga Free Press merged, the joint company was inaptly named Chattanooga News-Free Press, which could be interpreted as meaning that their newspapers were news-free.
An exception to the use of en dashes is usually made when prefixing an already-; an en dash is generally avoided as a distraction in this case. Examples of this include:
An en dash can be retained to avoid ambiguity, but whether any ambiguity is plausible is a judgment call. AMA style retains the en dashes in the following examples:
As discussed above, the en dash is sometimes recommended instead of a hyphen in compound adjectives where neither part of the adjective modifies the other—that is, when each modifies the noun, as in love–hate relationship.
The Chicago Manual of Style, however, limits the use of the en dash to two main purposes:
That is, the CMOS favors hyphens in instances where some other guides suggest en dashes, the 16th edition explaining that "Chicago's sense of the en dash does not extend to between", to rule out its use in "US–Canadian relations".
In these two uses, en dashes normally do not have spaces around them. Some make an exception when they believe avoiding spaces may cause confusion or look odd. For example, compare "12 June – 3 July" with "12 June–3 July". However, other authorities disagree and state there should be no space between an en dash and the adjacent text. These authorities would not include a space in the following examples: "11:00 a.m.⁠–⁠1:00 p.m." and "July 9–August 17".

Parenthetic and other uses at the sentence level

Like em dashes, en dashes can be used instead of colons or pairs of commas that mark off a nested clause or phrase. They can also be used around parenthetical expressions such as this one in place of the em dashes preferred by some publishers, particularly where short columns are used, since em dashes can look awkward at the end of a line. In these situations, en dashes must have a single space on each side.
Itemization mark
Either the en dash or the em dash may be used as a bullet at the start of each item in a bulleted list.

Typography

Spacing

In most uses of en dashes, such as when used in indicating ranges, they are closed up to the joined words. It is only when en dashes take the role of em dashes – for example, in setting off parenthetical statements such as this one – that they take spaces around them. For more on the choice of em versus en in this context, see [|En dash versus em dash].

Encoding and substitution

When an en dash is unavailable in a particular character encoding environment—as in the ASCII character set—there are some conventional substitutions. Often two hyphens are the substitute.
In Unicode, the en dash is U+2013. In HTML, one may use the numeric forms – or –; there is also the HTML entity –.
The en dash is sometimes used as a substitute for the minus sign, when the minus sign character is not available since the en dash is usually the same width as a plus sign. For example, the original 8-bit Macintosh Character Set had an en dash, useful for the minus sign, years before Unicode with a dedicated minus sign was available. The hyphen-minus is usually too narrow to make a typographically acceptable minus sign. However, the en dash cannot be used for a minus sign in programming languages because the syntax usually requires a hyphen-minus.

Em dash

The em dash, em rule, or mutton dash is longer than an en dash. The character is called an em dash because it is one em wide, a length that varies depending on the font size. One em is the same length as the font's height. So in 9-point type, an em dash is nine points wide, while in 24-point type the em dash is 24 points wide. By comparison, the en dash, with its width, is in most fonts either a half-em wide
or the width of an upper-case "N".

Usage

The em dash is used in several ways. Primarily in places where a set of parentheses or a colon might otherwise be used, it can show an abrupt change in thought or be used where a full stop is too strong and a comma too weak. Em dashes are also used to set off summaries or definitions. Common uses and definitions are cited below with examples.

Colon-like use

Simple equivalence (or near-equivalence) of colon and em dash
Simple equivalence (or near-equivalence) of paired parenthetical marks
It may indicate an interpolation stronger than that demarcated by parentheses, as in the following from Nicholson Baker's The Mezzanine.
Interruption by someone else
In this use, it is sometimes doubled:
"I'm aware of your mitigating circumstances, but your negative attitude was excessive."
In a related use, it may visually indicate the shift between speakers when they overlap in speech. For example, the em dash is used this way in Joseph Heller's Catch-22:
"Crazy!" Clevinger interrupted, shrieking. "That's what you are! Crazy!"
"—immense. I'm a real, slam-bang, honest-to-goodness, three-fisted humdinger. I'm a bona fide supraman."
Self-interruption
Quotation mark-like use
This is a quotation dash. It may be distinct from an em dash in its coding. It may be used to indicate turns in a dialog, in which case each dash starts a paragraph. It replaces other quotation marks, and was preferred by authors such as James Joyce:
Attribution of quote source
An em dash may be used to indicate omitted letters in a word redacted to an initial or single letter or to fillet a word, by leaving the start and end letters whilst replacing the middle letters with a dash or dashes. In this use, it is sometimes doubled.
Three em dashes might be used to indicate a completely missing word.

Itemization mark

Either the en dash or the em dash may be used as a bullet at the start of each item in a bulleted list, but a plain hyphen is more commonly used.

Repetition

Three em dashes one after another can be used in a footnote, endnote, or another form of bibliographic entry to indicate repetition of the same author's name as that of the previous work, which is similar to the use of ibid.

Typographic details

Spacing and substitution

According to most American sources and some British sources, an em dash should always be set closed, meaning it should not be surrounded by spaces. But the practice in some parts of the English-speaking world, including the style recommended by The New York Times Manual of Style and Usage for printed newspapers and the AP Stylebook, sets it open, separating it from its surrounding words by using spaces or hair spaces when it is being used parenthetically. The AP Stylebook rejects the use of the open em dash to set off introductory items in lists. However, the "space, en dash, space" sequence is the predominant style in German and French typography.
In Canada, The Canadian Style: A Guide to Writing and Editing, The Oxford Canadian A to Z of Grammar, Spelling & Punctuation: Guide to Canadian English Usage, Editing Canadian English, and the Canadian Oxford Dictionary all specify that an em dash should be set closed when used between words, a word and numeral, or two numerals.
The Australian government's Style Manual for Authors, Editors and Printers, also specifies that em dashes inserted between words, a word and numeral, or two numerals, should be set closed. A section on the 2-em rule also explains that the 2-em can be used to mark an abrupt break in direct or reported speech, but a space is used before the 2-em if a complete word is missing, while no space is used if part of a word exists before the sudden break. Two examples of this are as follows :
Monospaced fonts that mimic the look of a typewriter have the same width for all characters. Some of these fonts have em and en dashes that more or less fill the monospaced width they have available. For example, the sequence "hyphen, en dash, em dash, minus" shows as in a monospace font.

Approximating the em dash with two or three hyphens

When an em dash is unavailable in a particular character encoding environment—as in the ASCII character set—it has usually been approximated as a double or triple hyphen-minus. The two-hyphen em dash proxy is perhaps more common, being a widespread convention in the typewriting era.. The three-hyphen em dash proxy was popular with various publishers because the sequence of one, two, or three hyphens could then correspond to the hyphen, en dash, and em dash, respectively.
Because early comic book letterers were not aware of the typographic convention of replacing a typewritten double hyphen with an em dash, the double hyphen became traditional in American comics. This practice has continued despite the development of computer lettering.

En dash versus em dash

The en dash is wider than the hyphen but not as wide as the em dash. An em width is defined as the point size of the currently used font, since the M character is not always the width of the point size. In running text, various dash conventions are employed: an em dash—like so—or a spaced em dash — like so — or a spaced en dash – like so – can be seen in contemporary publications.
Various style guides and national varieties of languages prescribe different guidance on dashes. Dashes have been cited as being treated differently in the US and the UK, with the former preferring the use of an em dash with no additional spacing and the latter preferring a spaced en dash. As examples of the US style, The Chicago Manual of Style and The Publication Manual of the American Psychological Association recommend unspaced em dashes. Style guides outside the US are more variable. For example, The Elements of Typographic Style by Canadian typographer Robert Bringhurst recommends the spaced en dash – like so – and argues that the length and visual magnitude of an em dash "belongs to the padded and corseted aesthetic of Victorian typography".
In the United Kingdom, the spaced en dash is the house style for certain major publishers, including the Penguin Group, the Cambridge University Press, and Routledge. However, this convention is not universal. The Oxford Guide to Style acknowledges that the spaced en dash is used by "other British publishers" but states that the Oxford University Press, like "most US publishers", uses the unspaced em dash.
The en dash – always with spaces in running text when, as discussed in this section, indicating a parenthesis or pause – and the spaced em dash both have a certain technical advantage over the unspaced em dash. Most typesetting and word processing expects word spacing to vary to support full justification. Alone among punctuation that marks pauses or logical relations in text, the unspaced em dash disables this for the words it falls between. This can cause uneven spacing in the text, but can be mitigated by the use of thin spaces, hair spaces, or even zero-width spaces on the sides of the em dash. This provides the appearance of an unspaced em dash, but allows the words and dashes to break between lines. The spaced em dash risks introducing excessive separation of words. In full justification, the adjacent spaces may be stretched, and the separation of words further exaggerated. En dashes may also be preferred to em dashes when text is set in narrow columns, such as in newspapers and similar publications, since the en dash is smaller. In such cases, its use is based purely on space considerations and is not necessarily related to other typographical concerns.
On the other hand, a spaced en dash may be ambiguous when it is also used for ranges, for example, in dates or between geographical locations with internal spaces.

Horizontal bar

The horizontal bar, also known as a quotation dash, is used to introduce quoted text. This is the standard method of printing dialogue in some languages. The em dash is equally suitable if the quotation dash is unavailable or is contrary to the house style being used.
There is no support in the standard TeX fonts, but one can use \hbox\kern-.5em--- instead, or simply an em dash.

Swung dash

The swung dash resembles a lengthened tilde, and is used to separate alternatives or approximates. In dictionaries, it is frequently used to stand in for the term being defined. A dictionary entry providing an example for the term henceforth might employ the swung dash as follows:
There are several similar, related characters:
Typewriters and early computers have traditionally had only a limited character set, often having no key that produces a dash. In consequence, it became common to substitute the nearest available punctuation mark or symbol. Em dashes are often represented in British usage by a single hyphen-minus surrounded by spaces, or in American usage by two hyphen-minuses surrounded by spaces.
Modern computer software typically has support for many more characters and is usually capable of rendering both the en and em dashes correctly—albeit sometimes with an inconvenient input method. Some software, though, may operate in a more limited mode. Some text editors, for example, were restricted to working with a single 8-bit character encoding, and when unencodable characters are entered—for example by pasting from the clipboard—they were often blindly converted to question marks. Sometimes this happened to em and en dashes, even when the 8-bit encoding supported them or when an alternative representation using hyphen-minuses is an option.
Techniques for generating em and en dashes in various operating systems, word processors and markup languages are provided in the following table:

Similar Unicode characters

SampleRepeated for clarityUnicodeNameRemark
------U+002DThe standard ASCII hyphen. Sometimes this is used in groups to indicate different types of dash.
In programming languages, it is the character usually used to denote operators like the subtraction or the negative sign.
______U+005FA spacing character usually showing a horizontal line below the baseline. It is commonly used within URLs and identifiers in programming languages, where a space-like separation between parts is desired but a real space is not appropriate. As usual for ASCII characters, this character shows a considerable range of glyphic variation; therefore, whether sequences of this character connect depends on the font used.
~~~~~~U+007EUsed in programming languages.
Its glyphic representation varies, therefore for punctuation in running text the use of more specific characters is preferred, see above.
U+00ADUsed to indicate where a line may break, as in a compound word or between syllables.
¯¯¯¯¯¯U+00AFA horizontal line positioned at cap height usually having the same length as. It is a spacing character, related to the diacritic mark "macron". A sequence of such characters is not expected to connect, unlike.
ˉˉˉˉˉˉU+02C9A phonetic symbol.
ˍˍˍˍˍˍU+02CDA phonetic symbol.
˗˗˗˗˗˗U+02D7A variant of the minus sign used in phonetics to mark a retracted or backed articulation. It may show small end-serifs.
˜˜˜˜˜˜U+02DCA spacing clone of tilde diacritic mark.
‐‐‐‐‐‐U+2010The character that can be used to unambiguously represent a hyphen.
‑‑‑‑‑‑U+2011Also called "hard hyphen", denotes a hyphen after which no word wrapping may apply. This is the case where the hyphen is part of a trigraph or tetragraph denoting a specific sound, or where specific orthographic rules prevent a line break.
‒‒‒‒‒‒U+2012Similar to an en dash, but with exactly the width of a digit in the chosen typeface. The vertical position may also be centered on the zero digit, and thus higher than the en dash and em dash, which are appropriate for use with lowercase text in a vertical position similar to the hyphen. The figure dash may therefore be preferred to the en dash for indicating a closed range of values.
‾‾‾‾‾‾U+203EA character similar to, but a sequence of such characters usually connects.
⁃⁃⁃⁃⁃⁃U+2043A short horizontal line used as a list bullet.
⁻⁻⁻⁻⁻⁻U+207BUsually is used together with superscripted numbers.
₋₋₋₋₋₋U+208BUsually is used together with subscripted numbers.
−−−−−−U+2212An arithmetic operation used in mathematics to represent subtraction or negative numbers. Its glyph is consistent with the glyph of the plus sign, and it is centred on the zero digit, unlike the ASCII hyphen-minus and, that are designed to match lowercase letters and are inconsistent with arithmetic operators.
∼∼∼∼∼∼U+223CUsed in mathematics. Ends not curved as much regular tilde. In TeX and LaTeX, this character can be expressed using the math mode command $\sim$.
⎯⎯⎯⎯⎯⎯U+23AFMiscellaneous Technical. Can be used in sequences to generate long connected horizontal lines.
⏤⏤⏤⏤⏤⏤U+23E4Miscellaneous Technical. Represents line straightness in technical context.
──────U+2500Box-drawing characters. Several similar characters from one Unicode block used to draw horizontal lines.
➖➖➖➖➖➖U+2796Unicode symbols.
⸺⸺⸺⸺⸺⸺U+2E3ASupplemental Punctuation.
⸻⸻⸻⸻⸻⸻U+2E3BSupplemental Punctuation.
??????U+10191Uncia. A symbol for an ancient Roman unit of length.

Similar Unicode characters used in specific writing systems

is a hyphen from the Mongolian Todo alphabet.
is an Ancient Greek textual symbol, usually displayed by a long low line.
is used in ancient Near-Eastern linguistics.
is used mostly in German dictionaries and indicates umlaut of the stem vowel of a plural form.
is used in the transcription of old German manuscripts.
or are Hangul letters used in Korean to denote the sound.
and are wavy lines found in some East Asian character sets. Typographically, they have the width of one CJK character cell, and follow the direction of the text, being horizontal for horizontal text, and vertical for columnar. They are used as dashes, and occasionally as emphatic variants of the katakana vowel extender mark.
, the Japanese chōonpu, is used in Japanese to indicate a long vowel.
, the Chinese character for "one", is used in various East Asian languages.
looks like a sequence of a hyphen and a full stop.
is a compatibility character for a vertical em dash used in East Asian typography.
is a compatibility character for a vertical en dash used in East Asian typography.
is a compatibility character for a small em dash used in East Asian typography.
is a compatibility character for a wide tilde used in East Asian typography.
is a compatibility character for a small hyphen-minus used in East Asian typography.
is a compatibility character for a wide hyphen-minus used in East Asian typography.

In other languages

In many languages, such as Polish, the em dash is used as an opening quotation mark. There is no matching closing quotation mark; typically a new paragraph will be started, introduced by a dash, for each turn in the dialog.
Corpus studies indicate that em dashes are more commonly used in Russian than in English. In Russian, the em dash is used for the present copula, which is unpronounced in spoken Russian.
In French, em or en dashes can be used as parentheses, but the use of a second dash as a closing parenthesis is optional. When a closing dash is not used the sentence is ended with a period as usual. Dashes are, however, much less common than parentheses.
In Spanish, em dashes can be used to mark off parenthetical phrases. Unlike in English, the em dashes are spaced like brackets, i.e., there is a space between main sentence and dash, but not between parenthetical phrase and dash.
"Llevaba la fidelidad a su maestro –un buen profesor– hasta extremos insospechados."