|Definition - The name for the - symbol.|
1. Use it with compound adjectives.
2. Use it with compound numbers.
forty-seven and fifty-three
3. Use it to avoid confusion.
re-sign a petition (to avoid confusing it with resign, as in "resign from a job")
4. Use it with the prefix non except in cases where the prefix has become part of the word.
non-standard, non-American, non-verbal, non-stop
nondescript, nonage, nonentity, nonsense
5. Use it to avoid an awkward combinations of letters.
6. Use it with the prefixes self, all, and ex (meaning former).
self-possessed, all-inclusive, and ex-wife
7. Use it with the suffix elect.
8. Use it between a prefix and a capitalized word.
pre-Civil War, mid-October, and Afro-Canadian
9. Use it to separate a prefix or a suffix from a number.
mid-1980s and 60-ish
10. With abbreviations that use periods, retain the periods.
11. Use them between the letters of a spelled word.
A native of Burnaby is a B-u-r-n-a-b-e-i-n-g.
12. Use hyphens with fractions only when the fraction is an adjective.
Three-quarters of all car dealers eat potato chips (bad — here three-quarters is a noun, so it doesn't need a hyphen)
Three quarters of all car dealers eat potato chips. (good)
A three-quarters majority ate potato chips. (good — here it is an adjective, so it gets a hyphen)
Etymology - The word hyphen literally means "under one"; it derives from the Greek hypo, under + hen, one.
Oxford English Dictionary - Its first citation is from 1603:
"He would have us to reade these two last words in one, by way of hyphen, thus."
(Holland Plutarch's Mor., 41)