Punctuation Rules for Hyphens in English

Using Hyphens as Punctuation Marks in Written American English

Mar 18, 2010
Heather Marie Kosur

Hyphen - Heather Marie Kosur

The following article explains and exemplifies the rules for using hyphens in written American English.

Punctuation marks, as a convention of written language, function to ensure the clarity of writing for readers and writers. There are seven rules for using hyphens as punctuation marks in written American English:

With affixes
In compound nouns
In coequal nouns
In compound modifiers
In phrasal modifiers
In numbers
To avoid confusion and misreading

The following sections explain and provide examples of the punctuation rules for hyphens in written English.

Hyphens With Affixes

Use a hyphen between certain prefixes and suffixes such as all-, anti-, -elect, ex-, mid-, neo-, non-, post-, pre-, pro-, and self- and a noun. For example:

all-inclusive
ex-husband
non-English
president-elect

Use a hyphen between the prefixes anti-, mid-, neo-, post-, pre-, and pro- and a proper noun or number. For example:

anti-Christian
mid-1990s
neo-Nazism
post-colonialism

Usually use a hyphen between a prefix and a noun when the last letter of the prefix is the same as the first letter of the noun. For example:

anti-immigrant
de-emphasize
re-emerge
semi-independent

Do not use a hyphen with most other prefixes and suffixes. When in doubt, check a dictionary for standard hyphen use.

Hyphens in Compound Nouns

Use a hyphen in some compound nouns. For example:

court-martial
father-in-law
merry-go-round
T-shirt

When in doubt, consult a dictionary to determine if a compound noun requires a hyphen.

Hyphens in Coequal Nouns

Use a hyphen to join two or more coequal nouns. Coequal nouns are defined as pairs of nouns that are equal in function. For example:

singer-songwriter
teacher-poet
actor-director
writer-illustrator

Do not use a hyphen to join two or more nouns in which the first noun functions as a noun phrase modifier of the second noun.

Hyphens in Compound Modifiers

Use a hyphen to join compound noun phrase modifiers that precede a noun especially when (1) adverbs such as better, best, ill, lower, little, and well modify an adjective, (2) the second word is a present participle or past participle of a verb, and (3) the compound modifier contains a number. For example:

blue-collar worker
self-fulfilling prophecy
ill-prepared student
well-behaved toddler
forth-floor office
sports-hating aunt

Do not use a hyphen to join compound noun phrase modifiers that follow the noun. Also do not use a hyphen to join an adjective to an adverb ending in -ly or to the adverbs too, very, or much.

Hyphens in Phrasal Modifiers

Use a hyphen to separate words in a phrase that is functioning as a noun phrase modifier that precedes a noun. For example:

The cruise ship offers an all-you-can-eat seafood buffet.
Childbirth can be an out-of-this-world experience.
My doctor prescribed me an over-the-counter medication.
He has a stronger-than-he-looks outlook on life.

Hyphens in Numbers

Use a hyphen in the number between twenty-one and ninety-nine. For example:

twenty-two
thirty-seven
fifty-nine
ninety-eight

Use a hyphen to separate the numerator from the denominator in a fraction. For example:

one-half
three-fourths
nine-sixteenths
twelve-thirty-sevenths

Hyphens to Avoid Confusion

Use a hyphen to avoid confusion and misreading including awkward letter combinations. For example:

un-ionized (not ionized instead of unionized)
re-sign (sign again instead of resign)
Spanish-speaking student (student who speaks Spanish, not a student from Spain who speaks)
one-week vacation (vacation that is a week long, not a single week-long vacation)

Punctuation marks are a convention of written language that helps readers and writers more clearly understand writing by ensuring the clarity of writing. Hyphens perform seven basic functions in written American English: with affixes, in compound nouns, in coequal nouns, in compound modifiers, in phrasal modifiers, in numbers, and to avoid confusion and misreading.

Sources

Faigley, Lester. The Brief Penguin Handbook. New York: Pearson Longman. 2003.

Gibaldi, Joseph. MLA Handbook for Writers of Research Papers. 6th ed. New York: The Modern Language Association of America. 2003.

Heather Marie Kosur, Heather Marie Kosur

Heather Marie Kosur - About Me I earned a BA in English studies with a minor in creative writing from Illinois State University in May 2007 and an MS in ...