How do I hyphenate compound words?

APA style follows the Merriam-Webster’s Collegiate Dictionary for spelling and hyphenation of compound words. You may use the Merriam-Webster online at the UT library: The APA Publication Manual, however, recognizes that because science and technology terms develop quickly, their hyphenation standards may outpace those of the dictionary.

The main purpose of hyphenating compound words is to avoid ambiguity. For instance, if you are managing the construction of a hike-and-bike trail and order “five mile markers,” you could receive “five-mile markers” or “five mile-markers.” When in doubt, think about the hyphen as a tool that helps clarify what you mean.

Here are some basic guidelines for hyphenating compound words:

1. Hyphenate compound adjectives that precede the term they modify.

Examples: ball-and-socket joint, counter-clockwise movement, 4-cycle engine

2. Hyphenate phrases used as adjectives that precede the term they modify.

Example: trial-and-error analysis

3. Hyphenate adjective-and-noun compounds that precede the term they modify.

Example: high-temperature gradient

4. Hyphenate compound verbs.

Examples: heal-treat, direct-connect

5. Do not hyphenate a compound with an adverb ending with -ly.

Examples: newly installed, instantly recognized

6. In general, do not hyphenate compound nouns (such as boiling point, building site, bevel gear, circuit breaker, etc.) except those composed of distinct engineering units of measurement, such as fool-candle, gram-caloric, volt-ampere, and the like. Of course, many compound nouns-such as flywheel and overflow-are written as one word.

7. Do not use hyphens to express a range of numbers. Write “10 to 15 cc” rather than “10-15 cc.”