Rule A.8: Hyphens, En Dashes, and Em Dashes

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TLR follows the rules set forth in CMOS. Below is a summary of those rules and common usage.

A.8(a): Hyphens (-)

How to determine whether a word should be hyphenated:

  1. First you should always look to Merriam Webster to see if the compound is generally recognized.
  2. Second, look to Rules 7.81–88 in CMOS. 
  3. Third, look to the large example table included in Rule 7.89 in CMOS. Note that one of these rules is that hyphens should be used where it would aid readability.
  4. Fourth, look to whether the word is hyphenated, open, or closed in preferred Bluebook Publishing Journals. But if the term is in M-W’s dictionary (and same part of speech, e.g., adjective), check TLR only.

Compounds should be hyphenated if doing so makes the writing easier to understand or reduces ambiguity. For example, hyphenate “small-businessmen” to show that the businessmen run small businesses rather than that they are physically small.

Note: Whether a compound should be hyphenated or not sometimes depends on how the compound is being used—most often whether it is being used as part of a phrasal adjective or as a noun. For example, compare “a first-quarter touchdown” with “The team scored in the first quarter.”

A.8(b): En Dashes (–)

**Please note TLR differs from Bluebook for this rule**

Always conform to CMOS, specifically Rules 6.78–6.84. Though The Bluebook allows for ranges to be indicated using either a hyphen or en dash, TLR uses en dashes for all ranges as suggested by CMOS 6.78.

A.8(c): Em Dashes (—)

Always conform to CMOS, specifically Rules 6.85–6.92.

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