Hyphenation Station: The Hyphenation of Prefixes in APA Style

 by Chelsea Lee

Most words with prefixes are written without a hyphen after the prefix in APA Style. The table below contains some of the most common prefixes, examples of correct usage, and examples of exceptions. A full list of prefixes (and suffixes) to which this rule applies appears in Table 4.2 of the Publication Manual. 

Prefix	Example	Exception
anti-	antianxiety	anti-intellectual
co-	coworker	co-occur
mid-	midpoint	mid-2016
non-	nonsignificant	non-White
post-	postpartum	post-graduate-level students
pre-	pretreatment	pre-1960
pro-	prowar	pro-choice
re-	reexamination	re-pair [to pair again]
un-	undiagnosable	un-American

A hyphen should be used with a prefix under the following conditions:

• The word could be misread without a hyphen (e.g., re-pair, meaning to pair again, vs. repair, meaning to fix).
• The double vowels aa, ii, oo, or uu would occur without a hyphen (e.g., anti-intellectual is correct, not antiintellectual).
• The word that follows the hyphen is capitalized (e.g., un-American).
• The word that follows the hyphen begins with a numeral (e.g., mid-2016).
• The word is shown as permanently hyphenated in Merriam-Webster’s dictionary (e.g., pro-choice).
• A prefix is being added to a compound word that is already hyphenated (e.g., adding post- to graduate-level students creates post-graduate-level students, but if the phrase is just graduate students [no hyphen] then adding post- as a prefix gives you the regular hyphenless postgraduate students).

For more information on hyphenation principles, see Section 4.13 of the Publication Manual, our FAQ, or leave a comment below. And stay tuned for more posts in our hyphenation station series!