The hyphen is a punctuation mark used to join words and to separate syllables of a single word. The use of hyphens is called hyphenation.
The hyphen is sometimes confused with dashes (en dash , em dash and others), which are wider, or with the minus sign , which is also wider and usually drawn a little higher to match the crossbar in the plus sign .
As an orthographic concept, the hyphen is a single entity. In character encoding for use with computers, it is represented in Unicode by any of several characters. These include the dual-use hyphen-minus, the soft hyphen, the nonbreaking hyphen, and an unambiguous form known familiarly as the "Unicode hyphen", shown at the top of the infobox on this page. The character most often used to represent a hyphen (and the one produced by the key on a keyboard) is called the "hyphen-minus" in the Unicode specification because it is also used as a minus sign. The name derives from its name in the original ASCII standard, where it was called "hyphen(minus)".
Etymology The word is derived from Ancient Greek (), syncopated from (), "in one" (literally "under one").. An () was an undertie-like sign written below two adjacent letters to indicate that they belong to the same word when it was necessary to avoid ambiguity, before word spacing was practiced.
History
The first known documentation of the hyphen is in the grammatical works of Dionysius Thrax. At the time, hyphenation was joining two pieces of text that might otherwise be read as two separate words by a low tie mark. This was necessary due to the ambiguity inherent in the lack of word spacing. In Greek these marks were known as enotikon, officially romanized as a hyphen. [Ellīnikós Organismós Typopoíīsīs, "Hellenic Organization for Standardization"]. [ELOT 743, 2ī Ekdosī, "ELOT 743, "]. ELOT (Athens), 2001.
With the introduction of word spacing in the Middle Ages, the hyphen, still written beneath the text, was used to connect two words that had been incorrectly separated by a space. With word spacing in play, a space is essentially the same function as an enotikon, rendering the enotikon unnecessary. This, plus the extra difficulty of using an enotikon in the closely-spaced lines of movable type, caused the greek-style hyphen to fall by the wayside.
The Middle Ages also saw the introduction of the , for words broken across lines, and also the compound-word hyphen, for forming hyphenated compounds. It is unclear, and a matter of scholarly debate, whether the compound-word hyphen came from the marginal hyphen or vice versa.
Johannes Gutenberg, in the publication of his famous 42-line Gutenberg Bible, heralding the age of movable type, used , "common to blackletter texts of the time", as the form of his hyphen. The Gutenberg Bible is noted for its perfect justification and regular spacing, which it achieves in part by hyphenating words without any additional rules that would constrain it from placing a hyphen anywhere in a word.
Use in English
The English language does not have definitive hyphenation rules, though various style guides provide detailed usage recommendations and have a significant amount of overlap in what they advise. Hyphens are mostly used to break single words into parts or to join ordinarily separate words into single words. Spaces are not placed between a hyphen and either of the elements it connects except when using a suspended or "hanging" hyphen that stands in for a repeated word (e.g., nineteenth- and writers). Style conventions that apply to hyphens (and dashes) have evolved to support ease of reading in complex constructions; editors often accept deviations if they aid rather than hinder easy comprehension.
The use of the hyphen in English compound nouns and verbs has, in general, been steadily declining. Compounds that might once have been hyphenated are increasingly left with spaces or are combined into one word. In 2007, the sixth edition of the Shorter Oxford English Dictionary removed the hyphens from 16,000 entries, such as fig-leaf (now fig leaf), pot-belly (now pot belly), and pigeon-hole (now pigeonhole); Oxford University Press reported that evidence from the Oxford English Corpus showed an increasing preference for open or closed forms over hyphenated forms.. The increasing prevalence of computer technology and the advent of the Internet have given rise to a subset of common nouns that might have been hyphenated in the past (e.g., toolbar, hyperlink, and pastebin). Merriam-Webster notes that many compounds have historically progressed from open forms to hyphenated forms and eventually to closed forms as they became more familiar and frequent.
Despite decreased use, hyphenation remains the norm in certain compound-modifier constructions and, among some authors, with certain prefixes (see below). Hyphenation is also routinely used as part of syllabification in justified texts to avoid unsightly spacing (especially in columns with narrow line lengths, as when used with newspapers).
Separating Justification and line-wrapping When flowing text, it is sometimes preferable to break a word into two so that it continues on another line rather than moving the entire word to the next line. The word may be divided at the nearest break point between syllables (syllabification) and a hyphen inserted to indicate that the letters form a word fragment, rather than a full word. This allows more efficient use of paper, allows flush appearance of right-side margins (justification) without oddly large word spaces, and decreases the problem of rivers. This kind of hyphenation is most useful when the width of the column (called the "line length" in typography) is very narrow. For example:
Justified textwithout hyphenation Justified textwith hyphenationWe, therefore, the representatives of the United States of America ... We, therefore, the tatives of the United States of America ...
Rules (or guidelines) for correct hyphenation vary between languages, and may be complex, and they can interact with other orthographic and typesetting practices. Hyphenation algorithms, when employed in concert with dictionaries, are sufficient for all but the most formal texts.
It may be necessary to distinguish an incidental line-break hyphen from one integral to a word being mentioned (as when used in a dictionary) or present in an original text being quoted (when in a critical edition), not only to control its word wrap behavior (which encoding handles with hard and soft hyphens having the same glyph) but also to differentiate appearance (with a different glyph). Webster's Third New International Dictionary and the Chambers Dictionary use a double hyphen for integral hyphens and a single hyphen for line-breaks, whereas Kromhout's Afrikaans–English dictionary uses the opposite convention. The Concise Oxford Dictionary (fifth edition) suggested repeating an integral hyphen at the start of the following line.
Prefixes and suffixes Prefixes (such as de-, pre-, re-, and non-A fairly comprehensive list, although not exhaustive, is given at Prefix > List of English derivational prefixes.) and suffixes (such as , , , and ) are sometimes hyphenated, especially when the unhyphenated spelling resembles another word or when the affixation is deemed misinterpretable, ambiguous, or somehow "odd-looking" (for example, having two consecutive monographs that look like the digraphs of English, like e+a, e+e, or e+i). Compounds formed with prefixes are often written solid, although hyphens may be used to prevent misreading or to clarify a compound's formation, meaning, or pronunciation. The treatment of particular compounds can change as usage becomes established.
The hyphen may be used between vowel letters (e.g., ee, ea, ei) to indicate that they do not form a digraph. Some words have both hyphenated and unhyphenated variants: /deescalate, /cooperation, /reexamine, /deemphasize, and so on. Words often lose their hyphen as they become more common, such as email instead of . When there are tripled letters, the hyphenated variant of these words is often more common (as in instead of ).
Closed-up style is avoided in some cases: possible homographs, such as recreation (fun or sport) versus (the act of creating again), retreat (turn back) versus (give therapy again), and (not in ion form) versus unionized (organized into trade unions); combinations with proper nouns or adjectives (, );.. acronyms (, ); or numbers (, ). Although is still hyphenated by both Dorland's and Merriam-Webster's Medical, the solid (that is, unhyphenated) styling (protooncogene) is a common variant, particularly among oncologists and geneticists.
A diaeresis may also be used in a like fashion, either to separate and mark off monographs (as in coöperation) or to signalize a vocalic terminal e (for example, Brontë). This use of the diaeresis peaked in the late 19th and early 20th centuries, but it was never applied extensively across the language: only a handful of diaereses, including coöperation and Brontë, are encountered with any appreciable frequency in English; thus reëxamine, reïterate, deëmphasize, etc. are seldom encountered. In borrowings from Modern French, whose orthography utilizes the diaeresis as a means to differentiate graphemes, various English dictionaries list the dieresis as optional (as in naive and naïve) despite the juxtaposition of a and i.
Syllabification and spelling Hyphens are occasionally used to denote syllabification, as in syl-la-bi-fi-ca-tion. (Similar to a hyphenation point.)
Similarly, hyphens may be used to indicate the spelling of a word, as in W-O-R-D to represent word.
In the 19th and early 20th centuries hyphens were also sometimes used to divide syllables in words from indigenous North American languages being transcribed into the Latin script, such as "Shuh-shuh-gah" (from Ojibwe zhashagi, "blue heron") in The Song of Hiawatha. Other styles of transcription, in use before and after this one, did not use hyphens this way. As the hyphenation is "usually syllable-by-syllable but sometimes not", it is difficult to ascertain if this was intended to communicate morphological information or "some perceived difference in prosody". John Wesley Powell's Introduction to the Study of Indian Languages from 1880 explicitly instructs this method of transcription for the documentation of American Indian languages: "Syllables should be separated by hyphens. In connected texts hyphens should be omitted." This somewhat archaic hyphenation style can still be found preserved in some contemporary place names such as that of Ah-gwah-ching, Minnesota.
Joining Compound modifiers
Compound modifiers are groups of two or more words that jointly modify the meaning of another word. When a compound modifier other than an adverb–adjective combination appears before a term, the compound modifier is often hyphenated to prevent misunderstanding, such as in player or paintings. Without the hyphen, there is potential confusion about whether the writer means a "player of American football" or an "American player of football" and whether the writer means paintings that are "little celebrated" or "celebrated paintings" that are little.Gary Blake and Robert W. Bly, The Elements of Technical Writing, p. 48. New York: Macmillan Publishers, 1993. Compound modifiers can extend to three or more words, as in candy, and can be adverbial as well as adjectival ( frightening). However, if the compound is a familiar one, it is usually unhyphenated. For example, some style guides prefer the construction high school students, to students.E.g. Although the expression is technically ambiguous ("students of a high school"/"school students who are high"), it would normally be formulated differently if other than the first meaning were intended. Noun–noun compound modifiers may also be written without a hyphen when no confusion is likely: grade point average and department store manager.