In general, the move is away from hyphenated words, whether used as nouns or adjectives:
Generally do not hyphenate when using a prefix with a word starting with a consonant.
Three rules are constant:
- Except for cooperate and coordinate, use a hyphen if the prefix ends in a vowel and the word that follows begins with the same vowel.
- Use a hyphen if the word that follows is capitalized.
- Use a hyphen to join doubled prefixes: sub-subparagraph.
- With words beginning with the prefix co-, retain the hyphen when forming nouns, adjectives, and verbs that indicate occupation or status, such as co-worker and co-founder.
- Use a hyphen to join doubled prefixes, as in sub-subparagraph.A hyphen is needed with compound words that must be distinguished from homonyms, such as in the case of recover and re-cover.
- Use a hyphen when the last letter of the prefix and the first letter of the following word are the same, such as with pre-engineering, pre-election, or pre-establish.
If not referenced in the above rules, follow Webster's New World College Dictionary, hyphenating if not listed there.
- prearrange, pregame, precook, premedical, predate
Hyphenate “part time” and “full time” only when used as adjectives:
- He is a part-time instructor in the English department.
- She works full time in the computer laboratory.
Use a hyphen to join two or more words serving as a single adjective before a noun:
- tree-ripened peach
- well-qualified instructor
- a one-way road
However, when compound modifiers come after a noun, they are not hyphenated:
- The peach was tree ripened.
- The instructor is well qualified.
- The road is one way.
Do not use a hyphen to connect an adverb ending in “ly” to the adjective it modifies
- highly qualified student
- elegantly furnished home
When omitting the second part of a hyphenated term, retain the hyphen and follow with a space:
- 10- to 12-year-olds
- Hartford- or Greenwich-bound lane
Do not hyphenate “grade point average.”
Do not hyphenate the term “vice president.”
Do not hyphenate African American, Asian American, etc. when used as a noun.
Hyphenate study abroad when used as an adjective only (study-abroad programs)
Hyphenate service-learning in all uses.
For rules about capitalizing hyphenated words in a title or headline, see our capitalization section.