Interpunct

An interpunct Template:Char, also known as an interpoint, middle dot, middot, or centered dot, is a punctuation mark consisting of a vertically centered dot used for interword separation in Classical Latin. (Word-separating spaces did not appear until some time between 600 and 800Template:NbspCE.) It appears in a variety of uses in some modern languages.

The multiplication dot or "dot operator" is frequently used in mathematical and scientific notation, and it may differ in appearance from the interpunct.

In written language

Various dictionaries use the interpunct (in this context, sometimes called a hyphenation point) to indicate where to split a word and insert a hyphen if the word doesn't fit on the line. There is also a separate Unicode character, Template:Unichar.

English

File:Mayflower Compact Bradford.jpg

Bradford's transcription of the Mayflower Compact

In the early modern era, full stops (periods) were sometimes written as interpuncts (for example in the depicted 1646 transcription of the Mayflower Compact).

In British typography, the space dot was once used as the formal decimal point. Its use was advocated by laws and can still be found in some UK-based academic journals such as The Lancet. In the 1960s, this usage was advocated by the School Mathematics Project, and continues to be used, albeit inconsistently, in primary-school mathematics education. When the pound sterling was decimalised in 1971, the official advice issued was to write decimal amounts with a raised point (for example, £21·48) and to use a decimal point "on the line" only when typesetting constraints made it unavoidable. However, this usage had already been declining since the 1968 ruling by the Ministry of Technology to use the full stop as the decimal point, not only because of that ruling but also because the standard UK keyboard layout (for typewriters and computers) has only the full stop.

In the artificially constructed Shavian alphabet, interpuncts are used instead of capitalization as the marker of proper nouns. The dot is placed at the beginning of a word.

Latin

The interpunct () was regularly used in classical Latin to separate words. In addition to the most common round form, inscriptions sometimes use a small equilateral triangle for the interpunct, pointing either up or down. It may also appear as a mid-line comma, similar to the Greek practice of the time. The interpunct fell out of use Template:Circa, and Latin was then written for several centuries.

Franco-Provençal

In Franco-Provençal (or Arpitan), the interpunct is used in order to distinguish the following graphemes:

• ch·, pronounced , versus ch, pronounced
• j·, pronounced , versus j, pronounced
• g· before e, i, pronounced , versus g before e, i, pronounced

French

In modern French, the interpunct is sometimes used for gender-neutral writing, as in for ("the male employees and the female employees").

Occitano-Romance

Catalan

File:Barcelona - Estació de Paral·lel (7495657866).jpg

Metro station Paral·lel in Barcelona

The ("flying point") is used in Catalan between two Ls in cases where each belongs to a separate syllable, for example , "cell". This distinguishes such "geminate Ls" (), which are pronounced , from "double L" (), which are written without the flying point and are pronounced Template:IPAblink. In situations where the flying point is unavailable, periods (as in ) or hyphens (as in ) are frequently used as substitutes, but this is tolerated rather than encouraged.

Historically, medieval Catalan also used the symbol Template:Char as a marker for certain elisions, much like the modern apostrophe (see Occitan below) and hyphenations.

There is no separate physical keyboard layout for Catalan: the flying point can be typed using Template:Key press in the Spanish (Spain) layout or with Template:Key press on a US English layout. On a mobile phone with a Catalan keyboard layout, the geminate L with a flying dot appears when holding down the Template:Key press key. It appears in Unicode as the pre-composed letters Template:Char (U+013F) and Template:Char (U+0140), but they are compatibility characters and are not frequently used or recommended.Template:Efn

Occitan and Gascon

In Occitan and Gascon, the interpunct (punt interior, literally, "inner dot", or ponch naut for "high / upper point") is used to distinguish the following graphemes:

• s·h, pronounced , versus sh, pronounced , for example, in des·har 'to undo' vs deishar 'to leave'
• n·h, pronounced , versus nh, pronounced , for example in in·hèrn 'hell' vs vinha 'vineyard'

Although it is considered to be a spelling error, a period is frequently used when a middle dot is unavailable: des.har, in.hèrn, which is the case for French keyboard layout.

In modern editions of Old Occitan texts, the apostrophe and interpunct are used to denote certain elisions that were not originally marked. The apostrophe is used with proclitic forms and the interpunct is used with enclitic forms:

• que·l (que lo, that the) versus qu'el (that he)
• From Bertran de Born's Ab joi mou lo vers e·l comens (translated by James H. Donalson):

Bela Domna·l vostre cors gens
E·lh vostre bel olh m'an conquis,
E·l doutz esgartz e lo clars vis,
E·l vostre bels essenhamens,
Que, can be m'en pren esmansa,
De beutat no·us trob egansa:
La genser etz c'om posc'e·l mon chauzir,
O no·i vei clar dels olhs ab que·us remir.

Domna·l = Domna, lo ("Lady, the": singular definite article)
E·lh = E li ("And the": plural definite article)
E·l = E lo ("And the")
E·l = E lo ("And the")

No·us = Non vos ("(do) not... you": direct object pronoun)
E·l = En lo ("in the")
No·i = Non i ("(do) not... there") // Que·us = Que vos ("that (I)... you")

O pretty lady, all your grace
and eyes of beauty conquered me,
sweet glance and brightness of your face
and all your nature has to tell
so if I make an appraisal
I find no one like in beauty:
most pleasing to be found in all the world
or else the eyes I see you with have dimmed.

Greek

Ancient Greek lacked spacing or interpuncts but instead ran all the letters together. By Late Antiquity, various marks were used to separate words, particularly the Greek comma.

In modern Greek, the ano teleia mark (Template:Langx; also known as Template:Langx) is the infrequently-encountered Greek semicolon and is properly romanized as such. In Greek text, Unicode provides the code point Template:Unichar; however, it is canonically equivalent to the interpunct.

The Hellenistic scholars of Alexandria first developed the mark for a function closer to the comma, before it fell out of use and was then repurposed for its present role.

Old Irish

In many linguistic works discussing Old Irish (but not in actual Old Irish manuscripts), the interpunct is used to separate a pretonic preverbal element from the stressed syllable of the verb, e.g. "gives". It is also used in citing the verb forms used after such preverbal elements (the prototonic forms), e.g. "carries", to distinguish them from forms used without preverbs, e.g. "carries". In other works, the hyphen (, ) or colon (, ) may be used for this purpose.

Ethiopic

The Geʽez (Ethiopic) script traditionally separates words with an interpunct of two vertically aligned dots, like a colon, but with larger dots: Template:Nobr (For example Template:Nobr Starting in the late 19th century the use of such punctuation has largely fallen out of use in favor of whitespace, except in formal hand-written or liturgical texts. In Eritrea the character may be used as a comma.

Tibetan

In Tibetan the interpunct, called (), is used as a morpheme delimiter.

Chinese

The interpunct or "partition sign" is used in Chinese (which generally lacks spacing between characters) to mark divisions in words transliterated from phonogram languages, particularly names. Some fonts and software render Template:Unichar as double-width if it is between double-width characters, Chinese standards recommend half-width between Arabic numerals. In Taiwan, the formal standard, as defined by CNS 11643, historically specified Template:Unichar, while Template:Unichar should be primarily used in Japanese contexts for separating Katakana words. When the Chinese text is romanized, the partition sign is simply replaced by a standard space or other appropriate punctuation. Thus, William Shakespeare is written as Template:Lang-zh and George W. Bush as Template:Lang-zh. Titles and other translated words are not similarly marked: Genghis Khan and Elizabeth II are simply Template:Lang-zh and Template:Lang-zh.

The partition sign is also used to separate book and chapter titles when they are mentioned consecutively: book first and then chapter.

Hokkien

In Pe̍h-ōe-jī for Taiwanese Hokkien, middle dot is often used as a workaround for the dot above right diacritic, since most early encoding systems did not support this diacritic. This is now encoded as Template:Unichar. Unicode did not support this diacritic until June 2005. Newer fonts often support it natively; however, the practice of using middle dot still exists. Historically, it was derived in the late 19th century from an older barred-o with curly tail as an adaptation to the typewriter.

Japanese

Interpuncts are often used to separate transcribed foreign names or words written in katakana. For example, "Beautiful Sunday" becomes (Template:Transliteration). A middle dot is also sometimes used to separate lists in Japanese instead of the Japanese comma. Dictionaries and grammar lessons in Japanese sometimes also use a similar symbol to separate a verb suffix from its root. While some fonts may render the Japanese middle dot as a square under great magnification, this is not a defining property of the middle dot that is used in China or Japan.

However, the Japanese writing system usually does not use space or punctuation to separate words (though the mixing of katakana, kanji and hiragana gives some indication of word boundary).

In Japanese typography, there exist two Unicode code points:

• Template:Unichar, with a fixed width that is the same as most kana characters, known as fullwidth.
• Template:Unichar

The interpunct also has a number of other uses in Japanese, including the following: to separate titles, names and positions: (Assistant Section Head · Suzuki); as a decimal point when writing numbers in kanji: ; as a slash when writing for "or" in abbreviations: ; in place of hyphens, dashes and colons when writing vertically; and in song lyrics to add a brief pause between syllables.

Korean

Interpuncts are used in written Korean to denote a list of two or more words, similarly to how a slash (/) is used to juxtapose words in many other languages. In this role it also functions in a similar way to the English en dash, as in , "American–Soviet relations". The use of interpuncts has declined in years of digital typography and especially in place of slashes, but, in the strictest sense, a slash cannot replace a middle dot in Korean typography.

Template:Unichar () is used more than a middle dot when an interpunct is to be used in Korean typography, though araea is technically not a punctuation symbol but actually an obsolete Hangul jamo. Because araea is a full-width letter, it looks better than middle dot between Hangul. In addition, it is drawn like the middle dot in Windows default Korean fonts such as Batang.

Runes

Runic texts use either an interpunct-like or a colon-like punctuation mark to separate words. There are two Unicode characters dedicated for this:

• Template:Unichar
• Template:Unichar

In mathematics and science

Up to the mid twentieth century, and sporadically even much later, the interpunct could be found used as the decimal point in British publications, such as tables of constants (e.g., "Template:Math").

In publications conforming to the standards of the International System of Units, as well as the multiplication sign (×), the centered dot (dot operator) can be used as a multiplication sign. Only a comma or full stop (period) may be used as a decimal marker. The centered dot can be used when multiplying units, as in Template:Math for the newton expressed in terms of SI base units. In the United States, the use of a centered dot for the multiplication of numbers or values of quantities is discouraged by NIST.

In mathematics, a small middle dot can be used to represent multiplication; for example, $x\cdot y$ for multiplying $x$ by $y$. When dealing with scalars, it is interchangeable with the multiplication sign (Template:Char), as long as the multiplication sign is between numerals such that it would not be mistaken as variable $x$. For instance, $2\cdot 3y$ means the same thing as $2\times 3y$. However, when dealing with vectors, the dot operator denotes a dot product (e.g. $\overrightarrow{x}\cdot \overrightarrow{y}$, a scalar), which is distinct from the cross product (e.g. $\overrightarrow{x}\times \overrightarrow{y}$, a vector).

The symbol is sometimes used to denote the "AND" relationship in formal logic and Boolean algebra, which can be seen as a special case of multiplication.

Another usage of this symbol in mathematics is with functions, where the dot is used as a placeholder for a function argument, in order to distinguish between the (general form of the) function itself and the value or a specific form of a function evaluated at a given point or with given specifications. For example, $f(\cdot )$ denotes the function $x\mapsto f(x)$, and $\theta (s,a,\cdot )$ denotes a partial application, where the first two arguments are given and the third argument shall take any valid value on its domain.

In computing, the middle dot is usually displayed (but not printed) to indicate white space in various software applications such as word processing, graphic design, web layout, desktop publishing or software development programs. In some word processors, interpuncts are used to denote not only hard space or space characters, but also sometimes used to indicate a space when put in paragraph format to show indentations and spaces. This allows the user to see where white space is located in the document and what sizes of white space are used, since normally white space is invisible so tabs, spaces, non-breaking spaces and such are indistinguishable from one another.

In chemistry, the middle dot is used to separate the parts of formulas of addition compounds, mixture salts or solvates (typically hydrates), such as of copper(II) sulphate pentahydrate, Template:Math. The middle dot should not be surrounded by spaces when indicating a chemical adduct.

The middot as a letter

A middot may be used as a consonant or modifier letter, rather than as punctuation, in transcription systems and in language orthographies. For such uses Unicode provides the code point Template:Unichar.

In Americanist phonetic notation, the middot is a more common variant of the colon Template:Angle bracket used to indicate vowel length. It may be called a half-colon in such usage. Graphically, it may be high in the letter space (the top dot of the colon) or centered as the interpunct. From Americanist notation, it has been adopted into the orthographies of several languages, such as Washo.

In the writings of Franz Boas, the middot was used for palatal or palatalized consonants, e.g. Template:Anglebracket for IPA [c].

In the Sinological tradition of the 36 initials, the onset 影 (typically reconstructed as a glottal stop) may be transliterated with a middot Template:Angle bracket, and the onset 喻 (typically reconstructed as a null onset) with an apostrophe Template:Angle bracket. Conventions vary, however, and it is common for 影 to be transliterated with the apostrophe. These conventions are used both for Chinese itself and for other scripts of China, such as ʼPhags-pa and Jurchen.

In the Canadian Aboriginal syllabics, a middle dot ⟨ᐧ⟩ indicates a syllable medial ⟨w⟩ in Cree and Ojibwe, ⟨y⟩ or ⟨yu⟩ in some of the Athapascan languages, and a syllable medial ⟨s⟩ in Blackfoot. However, depending on the writing tradition, the middle dot may appear after the syllable it modifies (which is found in the Western style) or before the syllable it modifies (which is found in the Northern and Eastern styles). In Unicode, the middle dot is encoded both as independent glyph Template:Unichar or as part of a pre-composed letter, such as in Template:Unichar. In the Carrier syllabics subset, the middle dot Final indicates a glottal stop, but a centered dot diacritic on -position letters transform the vowel value to , for example: Template:Unichar, Template:Unichar.

Similar symbols

Symbol	Character Entity	Numeric Entity	Unicode Code Point	LaTeX	Notes
·	Template:Tt	Template:Tt	U+00B7 Template:Sc	Template:Tt	The interpunct
ˑ		Template:Tt	U+02D1 Template:Sc		IPA interpunct symbol: the triangular middot.
·		Template:Tt	U+0387 Template:Sc		Greek ánō stigmē
ּ		Template:Tt	U+05BC Template:Sc		Hebrew point dagesh or mapiq
᛫		Template:Tt	U+16EB Template:Sc		Runic punctuation
•	Template:Tt	Template:Tt	U+2022 Template:Sc	Template:Tt	bullet, often used to mark list items
‧		Template:Tt	U+2027 Template:Sc		hyphenation point (dictionaries)
∘	Template:Tt	Template:Tt	U+2218 Template:Sc	Template:Tt	ring operator (mathematics)
∙		Template:Tt	U+2219 Template:Sc	Template:Tt	bullet operator (mathematics)
⋅	Template:Tt	Template:Tt	U+22C5 Template:Sc	Template:Tt, Template:Tt	dot operator (mathematics)
⏺		Template:Tt	U+23FA Template:Sc		black circle for record
●		Template:Tt	U+25CF Template:Sc
◦		Template:Tt	U+25E6 Template:Sc		hollow bullet
⚫		Template:Tt	U+26AB Template:Sc		medium black circle
⦁		Template:Tt	U+2981 Template:Sc		symbol used by the Z notation
⸰		Template:Tt	U+2E30 Template:Sc		Avestan punctuation mark
⸱		Template:Tt	U+2E31 Template:Sc		word separator (Avestan and other scripts)
⸳		Template:Tt	U+2E33 Template:Sc		vertical position between full stop and middle dot
・		Template:Tt	U+30FB Template:Sc		fullwidth katakana middle dot
ꞏ		Template:Tt	U+A78F Template:Sc		as a letter
･		Template:Tt	U+FF65 Template:Sc		halfwidth katakana middle dot
𐄁		Template:Tt	U+10101 Template:Sc		word separator for Aegean scripts (Linear A and Linear B)

Characters in the Symbol column above may not render correctly in all browsers.

See also

• Punctuation
• Syllabification
• Dot (disambiguation)

External links

• Template:Commons category-inline