Conventionally, and with the support of modern writing guides, compound modifiers that appear
before a noun phrase should include a
hyphen between each word, subject to certain exceptions. Hyphens are used in this way to prevent confusion; without their use, a reader might interpret the words separately, rather than as a phrase. Hyphens join the relevant words into a single idea, a compound adjective. A compound modifier that is spaced rather than hyphenated is referred to as an . When a numeral and a noun are used in a compound modifier that precedes a noun, the noun in the modifier takes the singular form. For example, the
2021 Belmont Stakes was a "12-furlong race" and an "eight-horse race", not a "12-furlongs race" or an "eight-horses race".
Exceptions Major style guides advise consulting a dictionary to determine whether a compound adjective should be hyphenated; compounds entered as dictionary
headwords are permanent compounds, and for these, the dictionary's hyphenation should be followed even when the compound adjective follows a noun. According to some guides, hyphens are unnecessary in familiar compounds used as adjectives "where no ambiguity could result", while other guides suggest using hyphens "generally" in such compounds used as adjectives before nouns. It may be appropriate to distinguish between compound modifiers whose adverb has the
suffix -ly, such as
quickly and
badly, and those whose adverb does not, such as
well. The
-ly suffix on an adverb allows readers to understand its
lexical category (if not in the technical sense, then at least in the sense of the intended meaning), showing that it is intended to modify the adjective that it precedes and so not requiring hyphenation.
Quickly and
badly are unambiguously adverbs. Other adverbs (such as
well can commonly be used as adjectives; these adverbs without the
-ly suffix therefore commonly take a hyphen. For example, one could speak of a
well-known actress or a
little-known actress. If the compound modifier that would otherwise be hyphenated is changed to a post-modifier—one which is located after the modified noun phrase—then the hyphen is conventionally not necessary:
the actress is well known. Finally, the word
very in a compound modifier is generally not accompanied by a hyphen. Where both (or all) of the words in a compound modifier are nouns, it is seen as not necessary to hyphenate them, as misunderstanding is unlikely.
Examples •
Man-eating shark (as opposed to
man eating shark, which could be interpreted as a man eating the meat of a shark) •
Wild-goose chase (as opposed to
wild goose chase, which could be interpreted as a goose chase that is wild) •
Long-term contract (as opposed to
long term contract, which could be interpreted as a long contract about a term) •
Zero-liability protection (as opposed to
zero liability protection, which could be interpreted as there being no liability protection) •
College-football-halftime controversy (as opposed to
college-football halftime controversy, a controversy occurring during the halftime of a college-football match)
Examples using an en dash for attributive compounds An
en dash may be used for attributive compounds to enhance readability and eliminate ambiguity. •
Pulitzer Prize–winning novel •
New York–style pizza • The non–San Francisco part of the world • The post–World War II era • Pre–Civil War era •
Academy Award–nominated actor ==Other languages==