Hyphenation: Part II (Prefixes)
by Tina Blue
January 16, 2001
In an earlier article, "Hyphenation: Part I (Hyphenated Compounds)," I presented some of the situations where a hyphen is reliably required in phrases using written-out numbers or numerals. In this article I will deal with how to use hyphens with prefixes.
PREFIXES
A prefix attached to a common word usually becomes part of the word, so that the combination is written as one word.
I. COMMON PREFIXES
Most compounds made with the following prefixes are not hyphenated:
anti
intra
re
co
macro semi
de
micro sub
hyper non
supra
hypo
pre
trans
infra
pseudo un
EXAMPLES: antiwar, cochampion, coadministration, cochair, codiscover, comanagement, copayment, cofounders, copartners, cohabitate, coauthorship, decommission, debriefing, hyperactive, hypoallergenic, interpersonal, intramural, infrastructure, macroeconomics, macrocosm, microchip, microcosmic, predawn, prewar, prehistory, preadult, preverbal, prehuman, premeasure, prerequisite, pseudoclassic, pseudopregnancy, pseudosophisticated, pseudoscientific, realign, reread, reabsorb, reallocate, reassemble, reanimate, reapply, reappoint, semiautomatic, semiannual, semiarid, semiformal, semiliterate, subgenre, subacute, subcutaneous, subcontract, subcategory, subadult, transcontinental, transmontane, transoceanic, unappealing, unintentional, uninhibited, uninspiring, unimpressive.
EXCEPTIONS
A. Compounds with these prefixes are sometimes (but not always) hyphenated to avoid doubling a vowel or tripling a consonant, and sometimes even to prevent initial misreading or mispronunciation.
1. To avoid doubling a vowel:
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anti-art
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anti-administration
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co-opt (but cooperation)
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de-emphasize
2. To avoid tripling a consonant:
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shell-like
3. To prevent initial reading or mispronunciation:
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re-cover vs. recover (I will re-cover the sofa when I recover from the flu.)
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re-lay vs. relay (Relay the message. They will re-lay the tiles.)
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re-lease vs. release (Will you re-lease the apartment? Will they release the hostages?)
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either co-worker or coworker (but "coworker" could be initially misread as "cow-orker")
B. When one of these prefixes is combined with a word that begins with a capital letter, a hyphen is used to avoid having a capital letter in the middle of the word.
anti-American
un-Christian
pseudo-British
trans-European
trans-Atlantic
The alternative forms "transatlantic" and "unchristian" have become fairly common recently, but when in doubt, stick to the rule about hyphenating a prefix when the word it is attached to begins with a capital letter.
II. ALL AND SELF USED AS PREFIXES
When all and self are used as prefixes, they are usually hyphenated:
all-around 
all-American 
all-encompassing
all-wise 
all-knowing 
all-seeing
all-powerful 
self-image 
self-confident
self-examination
self-appointed 
self-styled
self-announced 
self-designated 
self-starter
III. WORDS WITH GREAT AND GRAND AS PREFIXES
A. When great is used as a prefix with kinship terms, it is hyphenated:
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great-aunt
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great-grandmother
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great-uncle
B. When grand is used as a prefix with kinship terms, it is sometimes hyphenated, sometimes not:
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grandmother
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grandfather
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grand-uncle
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grand-niece
IV. WORDS WITH HALF AS A PREFIX
Words with half as a prefix are usually, but not always, hyphenated :
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half-life
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half-asleep
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half-baked
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half-pound
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half-kilo
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half-hearted or halfhearted
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halfway
________________