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3 Spelling and hyphenation

3.3 Hyphenation

3.3.1 General principles

Since hyphenation often depends on the word’s or phrase’s role and its position in a sentence, and because it is to an extent dependent on adopted style or personal taste, it cannot be covered fully in a dictionary. This section sets out the basic principles and current thinking on hyphens.

3.3.2 Soft and hard hyphens

There are two types of hyphen. The hard hyphen joins words or parts of words together to form compounds (e.g. anti-nuclear, glow-worm, second-rate). Use of the hard hyphen is described in the rest of this section. The soft hyphen indicates word division when a word is broken at the end of a line; for the soft hyphen and word division see 3.4.

3.3.3 Compound words

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: Oxford Dictionaries Online specifies airstream rather than air-stream and air raid rather than air-raid, for example.

It is, of course, vital to make sure that individual forms are used consistently within a single text or range of texts. If an author has consistently applied a scheme of hyphenation, an editor need not alter it, although a text littered with hyphens can look fussy and dated. Editors can find the dominant form of a particular compound in a suitable current dictionary such as the New Oxford Dictionary for Writers and Editors.

Some compounds are hyphenated where there is an awkward collision of vowels or consonants:




but even here some are now typically written as one word:




Formerly in British English, a rule was followed whereby a combination of present participle and noun was spaced if the noun was providing the action (the walking wounded) but hyphenated if the compound itself was acted upon (a walking-stick—that is, the stick itself was not walking). The so-called ‘walking-stick rule’ is no longer borne out in common use: walking stick and many other such combinations (clearing house, colouring book, dining room) are now written as two words.

Compound modifiers that follow a noun do not need hyphens:

the story is well known

the records are not up to date

an agreement of long standing

poetry from the nineteenth century

but a compound expression preceding the noun is generally hyphenated when it forms a unit modifying the noun:

a well-known story

up-to-date records

a long-standing agreement

nineteenth-century poetry

A distinction may be made between compounds containing an adjective, such as first class or low level, and compound nouns, such as labour market: when compounds of the first sort are used before a noun they should be hyphenated (first-class seats, low-level radioactive waste), but the second sort need not be (labour market liberalization).

Compound adjectives formed from an adjective and a verb participle should be hyphenated whether or not they precede the noun:

double-breasted suits

Darren was quite good-looking

Where a compound noun is two words (e.g. a machine gun), any verb derived from it is normally hyphenated (to machine-gun). Similarly, compounds containing a noun or adjective that is derived from a verb (glass-making, nation-builder) are more often hyphenated than non-verbal noun or adjective compounds (science fiction, wildfire).

House styles vary greatly in their treatment of compound nouns and it is worth choosing a good dictionary such as the Oxford Dictionary of English or Oxford Dictionaries Online for guidance, but if a specific preference is not stated, it is as well to decide on your own choices for, e.g., decision maker/decision-making, and apply them consistently. Most styles seem to agree on policymaker but not on which to use out of policymaking, policy-making, or policy making for example. Much depends on the familiarity of the readership with a particular usage, for example the compound noun climate change would be unacceptable if hyphenated and jobseeker would jar as two words, at least in the UK, where Jobseeker’s Allowance is an accepted term. Agreement on the hyphenation of compound adjectives is more common:

decision-making process

cake-making equipment

but again there is a drift towards using one or two words

an international peacekeeping force

high quality teaching

unless ambiguous

cross-training of staff rather than cross training of staff

When a phrasal verb such as to hold up or to back up is made into a noun a hyphen is added or it is made into a one-word form (a hold-up, some backup). Note, however, that normal phrasal verbs should not be hyphenated:

continue to build up your pension

time to top up your mobile phone


continue to build-up your pension

time to top-up your mobile phone

Do not hyphenate adjectival compounds where the first element is an adverb ending in -ly:

a happily married couple

a newly discovered compound

Adverbs that do not end in -ly should be hyphenated when used in adjectival compounds before a noun, but not after a noun:

  • a tribute to the much-loved broadcaster

  • Dr Gray was very well known

Do not hyphenate italic foreign phrases unless they are hyphenated in the original language:

  • an ex post facto decision

  • an ad hominem argument

  • the collected romans-fleuves

  • a sense of savoir-vivre

Once foreign phrases have become part of the language and are no longer italicized, they are treated like any other English words, and hyphenated (or not) accordingly:

  • a laissez-faire policy

  • a bit of savoir faire

In general do not hyphenate capitalized compounds (although see 4.11.1):

  • British Museum staff

  • New Testament Greek

  • Latin American studies

Compound scientific terms are generally not hyphenated—they are either spaced or closed:

  • herpesvirus

  • radioisotope

  • liquid crystal display

  • sodium chloride solution

Capitalizing hyphenated compounds

When a title or heading is given initial capitals, a decision needs to be made as to how to treat hyphenated compounds. The traditional rule is to capitalize only the first element unless the second element is a proper noun or other word that would normally be capitalized:

  • First-class and Club Passengers

  • Anti-aircraft Artillery

In many modern styles, however, both elements are capitalized:

  • First-Class and Club Passengers

  • Anti-Aircraft Artillery

3.3.4 Prefixes and combining forms

Words with prefixes are often written as one word (predetermine, antistatic, subculture, postmodern), especially in US English, but use a hyphen to avoid confusion or mispronunciation, particularly where there is a collision of vowels or consonants:









but predate (existing before a certain date) despite potential confusion with the meaning to catch prey.

Note that cooperate, coordinate, and microorganism are generally written thus, despite the collision of os, and preoperative is used to accord with postoperative.

A hyphen is used to avoid confusion where a prefix is repeated (re-release, sub-subcategory) or to avoid confusion with another word (re-form/reform, re-cover/recover).

Hyphenate prefixes and combining forms before a capitalized name, a numeral, or a date:





When it denotes a previous state, ex- is usually followed by a hyphen, as in ex-husband, ex-convict. There is no satisfactory way of dealing with the type ex-Prime Minister, in which the second element is itself a compound. A second hyphen, e.g. ex-Prime-Minister, is not recommended, and rewording is the best option. The use of former instead of ex- avoids such problems, and is more elegant. Note that in US style an en rule is used to connect a prefix and a compound (the post–World War I period).

The prefix mid- is now often considered to be an adjective in its own right in such combinations as the mid nineteenth century; before a noun, of course, all compounds with mid should be hyphenated:

a mid-grey tone

a mid-range saloon car

Email and website are commonly one word (but web page); ebook is gaining ground over e-book but less familiar terms such as e-learning are currently hyphenated.

3.3.5 Suffixes

Suffixes are always written hyphenated or closed, never spaced.

The suffixes -less and -like need a hyphen if there are already two ls in the preceding word:



Use a hyphen in newly coined or rare combinations with -like, and with names, but more established forms, particularly if short, are set solid:







The suffixes -proof, -scape, and -wide usually need no hyphen:




When a complete word is used like a suffix after a noun, adjective, or adverb it is particularly important to use a hyphen, unless the word follows an adverb ending with -ly:

  • military-style ‘boot camps’

  • some banks have become excessively risk-averse

  • GPS-enabled tracking

  • an environmentally friendly policy

There can be a real risk of ambiguity with such constructions: compare

  • a cycling-friendly chief executive

  • rent-free accommodation in one of the pokey little labourer’s cottages

  • a cycling friendly chief executive

  • rent free accommodation in one of the pokey little labourer’s cottages

3.3.6 Numbers

Use hyphens in spelled-out numbers from 21 to 99:



For a full discussion of numbers see Chapter 11.

3.3.7 Compass points

Compass points are hyphenated:




but the compound names of winds are closed:



In US usage individual compass points are compound words:



Capitalized compounds are not usually hyphenated: note that, for example, South East Asia is the prevailing form in British English and Southeast Asia in US English.

3.3.8 Other uses

Use hyphens to indicate stammering, paused, or intermittent speech:

  • ‘P-p-perhaps not,’ she whispered.

  • ‘Uh-oh,’ he groaned.

Use hyphens to indicate an omitted common element in a series:

three- and six-cylinder models

two-, three-, or fourfold

upper-, middle-, and lower-class accents

countrymen and -women

When the common element may be unfamiliar to the reader, it is better to spell out each word:

  • ectomorphs, endomorphs, and mesomorphs

Hyphens are used in double-barrelled names:

  • Krafft-Ebing’s Psychopathia Sexualis (Krafft-Ebing is one man’s surname)

In compound nouns and adjectives derived from two names an en rule is usual (Marxism–Leninism), although for adjectives of this sort a hyphen is sometimes used (Marxist-Leninist). A hyphen, rather than an en rule, is always used where the first element of a compound cannot stand alone as an independent word, as in Sino-Soviet relations. See 4.11.1.

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