Using the Hyphen and the Dash

The Hyphen

The hyphen (-) is the small bar found on every keyboard. It has several related uses; in every case, it is used to show that what it is attached to does not make up a complete word by itself. The hyphen must never be used with white spaces at both ends, though in some uses it may have a white space at one end.

Most obviously, a hyphen is used to indicate that a long word has been broken off at the end of a line:

We were dismayed at having to listen to these utterly inconsequential remarks.

You should avoid such word splitting whenever possible. If it is unavoidable, try to split the word into two roughly equal parts, and make sure you split it at an obvious boundary. Do not write things like:







The first two of these are not broken at syllable boundaries, while the third is broken into two very unequal pieces. If you are in doubt as to where a word can be split, consult a dictionary. Many good dictionaries mark syllable boundaries to show you where words can be hyphenated. Some publishers even bring out hyphenation dictionaries containing no other information. Best of all, many word processors will perform hyphenation automatically, and you won't have to worry about it. In any case, note that a hyphen in such a case must be written at the end of its line, and not at the beginning of the following line.The hyphen is also used in writing compound words which, without the hyphen, would be ambiguous, hard to read or overly long. Here, more than anywhere else in the whole field of punctuation, there is room for individual taste and judgement; nevertheless, certain principles may be identified. These are:

(1) Above all, strive for clarity;

(2) Don't use a hyphen unless it's necessary;

(3) Where possible, follow established usage.

On this last point, consult a good dictionary; Collins or Longman is recommended, since the conservative Chambers and Oxford dictionaries frequently show hyphens which are no longer in normal use.Should you write land owners, land-owners or landowners? All are possible, and you should follow your judgement, but I prefer the third, since it seems unambiguous and easy to read, since it avoids the use of a hyphen and since this form is confirmed by Longman and Collins as the usual one (while Chambers, predictably, insists on the hyphenated form).

What about electro-magnetic versus electromagnetic? Collins and Longman confirm that only the second is in use among those who use the term regularly, but again Oxford clings stubbornly to the antiquated and pointless hyphen.

On the other hand, things like *pressurecooker, *wordprocessor and *emeraldgreen are impossibly hard on the eye; reference to a good dictionary will confirm that the established forms of the first two are pressure cooker and word processor, while the last is emerald green or emerald-green, depending on how it is used (see below).

The hyphen is regularly used in writing so-called "double-barrelled" names: José-María Olazábal, Jean-Paul Gaultier, Claude Lévi-Strauss, Philip Johnson-Laird. However, some individuals with such names prefer to omit the hyphen: Jean Paul Sartre, Hillary Rodham Clinton. You should always respect the usage of the owner of the name.

Now here is something important: it is usually essential to hyphenate compound modifiers. Compare the following:

She kissed him good night.

She gave him a good-night kiss.

The hyphen in the second example is necessary to show that good-night is a single compound modifier. Without the hyphen, the reader might easily be misled:Here the reader might be momentarily flummoxed into thinking that she had given him some kind of "night kiss", whatever that means. Here are some further examples:

Her dress is light green.

She's wearing a light-green dress.

This book token is worth ten pounds.

This is a ten-pound book token.

She always turned up for the parties at the end of term.

She always turned up for the end-of-term parties.

This essay is well thought out.

This is a well-thought-out essay.

Her son is ten years old.

She has a ten-year-old son.

Use hyphens liberally in such compound modifiers; they are often vital to comprehension: a light-green dress is not necessarily a light green dress; our first-class discussion is quite different from our first class discussion; a rusty nail cutter is hardly the same as a rusty nail-cutter; a woman-hating religion is utterly different from a woman hating religion; and a nude-review producer is most unlikely to be a nude review producer! You can mislead your reader disastrously by omitting these crucial hyphens: She always turned up for the end of term parties does not appear to mean the same as the hyphenated example above (example adapted from Carey 1958: 82). So make a habit of hyphenating your compound modifiers:

a long-standing friend

not *a long standing friend

well-defined rules

not *well defined rules

a copper-producing region

not *a copper producing region

a low-scoring match

not *a low scoring match

little-expected news

not *little expected news

a green-eyed beauty

not *a green eyed beauty

a rough-and-ready approach

not *a rough and ready approach

a salt-and-pepper moustache

not *a salt and pepper moustache

a far-ranging investigation

not *a far ranging investigation

her Swiss-German ancestry

not *her Swiss German ancestry

her new-found freedom

not *her new found freedom

the hang-'em-and-flog-'em brigade

not *the hang 'em and flog 'em brigade

The correct use or non-use of a hyphen in a modifier can be of vital importance in making your meaning clear. Consider the next two examples:

The earliest known hominid was Homo habilis.

The earliest-known hominid was Homo habilis.

These do not mean the same thing at all. The first means that, of all the hominids we know about, H. habilis was the earliest one to exist (but not necessarily the first one we knew about). The second means that, of all the hominids, H. habilis was the first one we knew about (but not necessarily the first one to exist). Effectively, the first sentence includes the structure [earliest] [known hominid], while the second includes the structure [earliest-known] [hominid]. Again, these two sentences would be pronounced differently, but the pronunciation difference is lost in writing; hence accurate punctuation is essential if you are not going to mislead your reader utterly. Punctuation is not a matter for personal taste and caprice, not if you want your readers to understand what you've written. (As it happens, the first statement is true, but the second one is false.)A compound modifier may also require a hyphen when it apears after the verb. Here is a splendid example from Carey (1958): Her face turned an ugly brick-red appears to mean something very different from Her face turned an ugly brick red. Old-fashioned usage, especially in Britain, favours excessive hyphenation, producing such forms as to-day, co-operate, ski-ing, semi-colon and even full-stop; such hyphens are pointless and ugly and should be avoided. Much better are today, cooperate, skiing, semicolon and full stop: don't use a hyphen unless it's doing some real work. Prefixes present special problems. She's repainting the lounge seems unobjectionable, but She's reliving her childhood is possibly hard to read and should perhaps be rewritten as She's re-living her childhood. And She re-covered the sofa [= `She put a new cover on the sofa'] is absolutely essential to avoid confusion with the entirely different She recovered the sofa [= `She got the sofa back']. The chemical term meaning `not ionized' is routinely written by chemists as unionized, but, in some contexts, you might prefer to write un-ionized to avoid possible confusion with the unrelated word unionized `organized into unions'. Use your judgement: put a hyphen in if you can see a problem without it, but otherwise leave it out. Here are a few examples of good usage:


but mini-aircraft


but non-negotiable


but pre-empt


but anti-aircraft

The hyphen is written only when the word would be hard to read without it: *nonnegotiable, *preempt. As always, consult a good dictionary if you're not sure.Observe, by the way, that a prefix must not be written as though it were a separate word. Thus all the following are wrong:

*post war period

*non communist countries

*mini computer

*anti vivisectionists

There are three cases in which a hyphen is absolutely required after a prefix. First, if a capital letter or a numeral follows:

non-EC countries

un-American activities

pre-Newtonian physics

anti-French feeling

post-Napoleonic Europe

pre-1500 English literature

Second, if the prefix is added to a word which already contains a hyphen:

non-bribe-taking politicians

his pre-globe-trotting days

non-stress-timed languages

an un-re-elected politician

Your reader cannot be expected to take in at a glance some indigestible glob like *his preglobe-trotting days or *an unre-elected politician.Third, if the prefix is added to a compound word containing a white space. In this case, the white space itself must be replaced by a hyphen to prevent the prefixed word from becoming unreadable:

seal killing

but anti-seal-killing campaigners

twentieth century

but pre-twentieth-century music

cold war

but our post-cold-war world

Again, your readers will not thank you for writing something like *antiseal killing campaigners or *our postcold-war world (or, still worse, *our postcold war world, a piece of gibberish I recently encountered in a major newspaper) . Who are these campaigners who kill antiseals, whatever those might be, and what is a war world and what is special about a postcold one?In any case, do not go overboard with large and complex modifiers. The cumbersome anti-seal-killing campaigners can easily be replaced by campaigners against seal-killing, which is much easier to read. The hyphen may also be used in representing ranges of numbers, and occasionally also other ranges. Printed books use a special symbol for this, the en dash (­), which is a little longer than a hyphen but still shorter than a full dash. Few keyboards can produce an en dash, however; if yours can't, you should use a hyphen instead (not a dash). A representation of the form X­Y means `from X to Y' or `between X and Y'. Here are some examples:

Steel contains 0.1­1.7 % carbon.

These fossils are 30­35 million years old.

The London­Brighton vintage car rally takes place on Sunday.

The declaration of the Rome­Berlin axis led to the use of the label `Axis powers' for Germany and Italy.

Do not write things like this:

*Steel contains from 0.1­1.7 % carbon.

*Steel contains between 0.1­1.7 % carbon.

These are terrible, since the sense of `from' or `between' is already included in the punctuation.Finally, the hyphen has one rather special use: it is used in writing pieces of words. Here are some examples:

The prefix re- sometimes requires a hyphen.

The suffix -wise, as in `moneywise' and `healthwise', has become enormously popular in recent years.

The Latin word rex `king' has a stem reg-.

Only when you are writing about language are you likely to need this use of the hyphen. If you do use it, make sure you put the hyphen at the correct end of the piece-of-a-word you are citing -- that is, the end at which the piece has to be connected to something else to make a word. And note that, when you're writing a suffix, the hyphen must go on the same line as the suffix itself: you should not allow the hyphen to stand at the end of its line, with the suffix on the next line. Word processors won't do this automatically, and you will need to consult your manual to find out how to type a hard hyphen, which will always stay where it belongs.There is, however, one very special case in which you might want to write a piece of a word in any kind of text. Consider the following example:

Pre-war and post-war Berlin could hardly be more different.

There is another way of writing this:

Pre- and post-war Berlin could hardly be more different.

This style is permissible, but observe that the now isolated prefix pre- requires a hyphen, since it is only a piece of a word.The same thing happens when you want to write a piece of a word which is not normally hyphenated, in order to avoid repetition:

Natalie is studying sociolinguistics and psycholinguistics.

This can also be written as follows:

Natalie is studying socio- and psycholinguistics.

The hyphen is also used in writing numerals and fractions.

The Dash

The dash (--), also called the em dash, is the long horizontal bar, much longer than a hyphen. Few keyboards have a dash, but a word processor can usually produce one in one way or another. If your keyboard can't produce a dash, you will have to resort to a hyphen as a stand-in. In British usage, we use only a single hyphen to represent a dash - like this. American usage, in contrast, uses two consecutive hyphens -- like this (A). Here I must confess that I strongly prefer the American style, since the double hyphen is far more more prominent than a single one and avoids any possibility of ambiguity. If you are writing for publication, you will probably have to use the single hyphen; in other contexts, you should consider using the more vivid double hyphen. In any case, you will be very unlucky if your word processor can't produce a proper dash and save you from worrying about this. There are two slightly different conventions for using a dash. The more modern one is to put white spaces at both ends of a dash, while the older style uses no white spaces at all, but writes the dash solid next to whatever precedes and follows it. Both conventions are in use, and hence you may see either of the following:

The Serbs want peace -- or so they say.

The Serbs want peace--or so they say.

I prefer the first style, since it is much easier on the eye, and I recommend that you adopt this style.The dash has only one use: a pair of dashes separates a strong interruption from the rest of the sentence. (A strong interruption is one which violently disrupts the flow of the sentence.) Again, note that word `pair': in principle, at least, dashes come in pairs, though sometimes one of them is not written. (Remember that the same thing is true of bracketing commas, which set off weak interruptions.) Here are some examples:

An honest politician -- if such a creature exists -- would never agree to such a plan.

The destruction of Guernica -- and there is no doubt that the destruction was deliberate -- horrified the world.

When the Europeans settled in Tasmania, they inflicted genocide -- there is no other word for it -- upon the indigenous population, who were wiped out in thirty years.

If the strong interruption comes at the end of the sentence, then of course only one dash is used:

In 1453 Sultan Mehmed finally took Constantinople -- and the Byzantine Empire disappeared from the map forever.

There was no other way -- or was there?

In the case in which the original sentence is never resumed after the interruption, only one dash is used:

John, do you suppose you could -- oh, never mind; I'll do it.

This sort of broken sentence is only found in representations of conversation, such as you might find in a novel; it is never appropriate in formal writing.Finally, in the rare case in which a sentence is broken off abruptly without being completed, a single dash is also used:

General Sedgwick's last words to his worried staff were "Don't worry, boys; they couldn't hit an elephant at this dist--".

Note that, in this case, the dash is written solid next to the unfinished piece-of-a-word which precedes it. (If the sentence merely tails off into silence, we use, not a dash, but a suspension.)When a dash falls between the end of one line and the beginning of the next, you should try to ensure that the dash is placed at the end of the first line and not at the beginning of the second, if you can. Most word processors will not do this automatically, however, and it will require some fiddling. That's all there is to know about the dash. Use the dash carefully: overuse of dashes will give your writing a breathless and disjointed appearance. And don't use a dash for any purpose other than setting off a strong interruption: the dash is never used in place of a hyphen, after a colon or after a heading. It is not used to introduce a direct quotation, except sometimes in novels, but this is not a usage you should imitate. There is one last point, very trivial. In a certain style of writing which is now felt to be antique and genteel, a dash is occasionally used to represent the omission of several letters from a word or a name. The exceedingly genteel Victorian novelists often wrote d--n in place of damn, and even Go to the d--l! instead of Go to the devil! Such usages strike us as comical now, and few writers today would hesitate to write out such mild oaths in full (but compare the related use of asterisks for the coarser words). Some Victorians, not wanting to set their fictional narratives in any identifiable location, also wrote things like At the time, I was living at B-- in the county of S--. This quaint affectation is now dead.