The Collaborative International Dictionary of English v.0.48:

Hyphen \Hy"phen\ (h[imac]"f[e^]n), n. [L., fr. Gr. "yfe`n, fr.
   "yf "e`n under one, into one, together, fr. ? under + ?,
   neut. of ? one. See Hypo-.] (Print.)
   A mark or short dash, thus [-], placed at the end of a line
   which terminates with a syllable of a word, the remainder of
   which is carried to the next line; or between the parts of
   many a compound word; as in fine-leaved, clear-headed. It is
   also sometimes used to separate the syllables of words.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Hyphen \Hy"phen\, v. t. [imp. & p. p. Hyphened; p. pr. & vb.
   n. Hyphening.]
   To connect with, or separate by, a hyphen, as two words or
   the parts of a word.
   [1913 Webster]

WordNet (r) 3.0 (2006):

hyphen
    n 1: a punctuation mark (-) used between parts of a compound
         word or between the syllables of a word when the word is
         divided at the end of a line of text [syn: hyphen,
         dash]
    v 1: divide or connect with a hyphen; "hyphenate these words and
         names" [syn: hyphenate, hyphen]