The hyphen (-) is much shorter than the en- or em-dash ( or ), and must never be used where those marks are required. Here again, many publishers are intent on removing hyphens wherever possible – but they have many valuable uses:

  1. To avoid ambiguity:
    • A re-formed theatre company is different to a reformed one.
    • To re-mark an assignment is different to making a remark about it.
    • A cross-section of the public, is not the same as a cross section of the public. [Ask any politician.]
    • A newspaper-style book: or a newspaper style-book. [Quite different.]
  2. For spelling out numbers, spelled-out words, and names:
    • Seventy-six trombones.
    • One hundred and ninety-five; one thousand, two hundred and forty-two.
    • Five-eighth; three-quarters; one-sixteenth.
    • One-quarter full [but: one quarter of the crowd].
    • Eight- and nine-year-olds [note the hanging hyphen].
    • Half-an-hour.
    • It’s spelled: H-Y-P-H-E-N.
    • I said, no! N-O, no!
    • W-what do you m-mean? [Indicating stammering.]
    • Anthony Armstrong-Jones; Catherine Zeta-Jones.
    Note: only spelled-out numbers between 21 and 99 are hyphenated.
  3. For certain prefixes, suffixes, and single letters:
    • Anti-American; anti-communist; un-Australian; anti-hero.
    • Quasi-political organisations; pseudo-religious groups.
    • Pro-business; ex-members; non-compliant; all-inclusive.
    • Mid-Atlantic; Neo-Gothic; post-Cretaceous.
    • Co-respondent (one party in a divorce). [But correspondent for letter writers.]
    • Australia-wide; trickle-down.
    • X-ray; U-turn; 3-D; H-bomb.
  4. When forming an adjective from a collection of words
    and certain phrases:
    • Once-in-a-lifetime opportunity.
    • Cost-of-living Index; rank-and-file members.
    • Up-to-date records; in-house exams; built-up area.
    • Run-of-the-mill; cat-o’-nine-tails; ne’er-do-well.
    • Mother-in-law; master-at-arms; toad-in-the-hole.
  5. To avoid unsightly or confusing letter combinations:
    • De-ice [far better than deice].
    • De-energise [deenergise simply looks silly].
    • Shell-like [as opposed to the ridiculous shelllike].
    • Co-worker [is a coworker a female whale?]
    • Re-enter; re-establish; re-examine.
    Note: words like co-operate and co-ordinate are now commonly given in many dictionaries as cooperate and coordinate, particularly in the US. However, there is still a case for hyphenating these. It would be foolish, for instance, to have codriver (co-driver) or coown (co-own) – so why not be consistent with our use of these prefixes in compound words?
  6. To split a word in two when it is forced by the typesetting on-
    to the next line (i.e. hypenation):

    This is one of the main functions of the hyphen, and compli-
    cated rules govern how this should be done. Good word-
    processors and page-layout programs have inbuilt diction-
    aries to automate their use.

Back to top …