Style Corner: 16 Tips on Hyphens and Dashes

This edition of Style Corner goes back to the topic of an earlier blog which looked at hyphens and dashes.

Hyphens can cause angst. The rules are, at best, complicated. And hang the rules, usage is complicated too. There is a generational split: older users prefer it, younger users demur.

Hart’s Rules on the hyphen are unusually apologetic and complex. To illustrate, check out Hart’s view on hyphenating noun compounds:

A compound term may be open (spaced as separate words), hyphenated, or closed (written as one word). However there is an increasing tendency to avoid hyphenation for noun compounds.

In this Style Corner we use the Always/Never/Sometimes construct, though this does miss some nuances.


There are some clearly-defined situations where we always use one, or should.

Tip 1
Where it would be ambiguous or misleading not to:
Re-cover (a chair) vs recover (from illness)

Tip 2
In a compound that has an adjective and a verb participle, before OR after a noun:
Foul-smelling waste; her husband was good-looking

Tip 3
In a compound that has an adjective but no verb participle, BEFORE a noun not after:
Twentieth-century boy; vs a boy from the twentieth century

Tip 4
In a compound with an adverb that is not -ly, BEFORE a noun not after:
A much-admired painting; vs a painting that was much admired

Tip 5
In a prefix or suffix where it would look plain ugly or wrong not to; for example due to too many of the same letters in a row; or where the suffix is a complete word adjoined to a noun, adjective or adverb:
Footballer-style haircut


I won’t bother repeating the obvious ones from above: the corollaries of Tips 1, 3 and 4. But here are some other Nevers.

Tip 6
In an adjectival compound that includes an -ly adverb:
Cleverly written

Tip 7
In compound terms relating to science:
Carbon dioxide

Tip 8
In a phrasal verb that is definitely a verb:
He wanted to build up his network

Tip 9
With the suffixes wide, scape and proof:
Countrywide, cityscape, foolproof


These are more controversial. The decisions are partly to do with usage but also with fashion and preference. Hyphenation isn’t always clear cut, even when it’s perceived to be.

Tip 10
In foreign phrases: yes, if the word has a hyphen in its original language: no, if not. But allow sense and instinct to dictate.
Sang-froid, sangfroid or sang froid
All are good. Let judgment be your guide. Just be consistent.

Tip 11
In a phrasal verb used as a noun:
The build-up of the network or
The build up of the network
These constructions are so close to being compound nouns that anything goes.

Tip 12
In spelled-out numbers:
Sixty-four or sixty four
Personally I think it’s a matter of preference and taste, whatever the rules say. It doesn’t look bad without, and is not ambiguous. Why insist?

Tip 13
In most other uses of compounds, prefixes and suffixes; just bear in mind Tips 1 to 5 and use one if it would be misleading or intolerably ugly not to. Aside from those instances a hyphen should be both allowed and not required, as long as consistency reigns in separate uses of the same word:
Anti-establishment or anti establishment
Copy-editor, copy editor or copyeditor
E-mail or email

For completeness we haven’t covered a few more obscure things like compass points, pauses, omissions, double barrelled surnames and others.

We’ll finish this section with some brief tips on dashes, the En dash (width of a letter n) – also called the En rule – and its American cousin the Em dash or Em rule (width of a letter m).

En dash

Tip 14
Use an En dash not a hyphen when compounding two things that have approximately equal weight and both could stand alone in their own right. This includes number ranges.
1939–1945 war
Kent–Surrey border
Or as a parenthetical divider, instead of brackets or commas.

Em dash

Tip 15
An Em dash is used in American English as an alternative to the parenthetical En dash. It has no preceding or following spaces—it closes up to both preceding and succeeding word.

This applies only to the parenthetical En dash, used either singly or in a pair. The ‘separating’ En dash – separating a number range or two adjoining but standalone elements in a compound, as in Tip 14 – remains an En dash in both British and American usage.

Tip 16
Finally the most important tip of the 16: be consistent.

Consistency is the only rule that really matters here, and covers a multitude of usages.

Prism hyphen Clarity?

One more thing: Prism-Clarity has a hyphen. Why, given Hart’s statement that in general capitalised compounds should not be hyphenated?

The answer is that this guidance is not definitive. Hart acknowledges that you can hyphenate. And if you do – and the first element of the compound is capitalised – then in modern usage the second element is often capitalised too. Hence Prism-Clarity with a hyphen.

In truth we chose a hyphen between Prism and Clarity because that web domain name was available. Everything else, including the company name, followed suit. It was a pragmatic judgment, which trumped anything linguistic rules or usage guides might offer.

Language is a living thing and we should allow it to live, breathe and evolve. If it is evolving away from hyphenation and other traditional forms we should accept that and temper our judgment; except where it really makes a difference to the meaning to have one or not (as in Tip 1 earlier).

Aside from that anything goes, but be consistent.