The Collaborative International Dictionary of English v.0.48:

Neither \Nei"ther\ (n[=e]"[th][~e]r or n[imac]"[th][~e]r; 277),
   a. [OE. neither, nother, nouther, AS. n[=a]w[eth]er,
   n[=a]hwae[eth]er; n[=a] never, not + hwae[eth]er whether. The
   word has followed the form of either. See No, and
   Whether, and cf. Neuter, Nor.]
   Not either; not the one or the other.
   [1913 Webster]

         Which of them shall I take?
         Both? one? or neither? Neither can be enjoyed,
         If both remain alive.                    --Shak.
   [1913 Webster]

         He neither loves,
         Nor either cares for him.                --Shak.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Neither \Nei"ther\, conj.
   Not either; generally used to introduce the first of two or
   more coordinate clauses of which those that follow begin with
   nor.
   [1913 Webster]

         Fight neither with small nor great, save only with the
         king.                                    --1 Kings
                                                  xxii. 31.
   [1913 Webster]

         Hadst thou been firm and fixed in thy dissent,
         Neither had I transgressed, nor thou with me. --Milton.
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         When she put it on, she made me vow
         That I should neither sell, nor give, nor lose it.
                                                  --Shak.
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   Note: Neither was formerly often used where we now use nor.
         "For neither circumcision, neither uncircumcision is
         anything at all." --Tyndale. "Ye shall not eat of it,
         neither shall ye touch it." --Gen. iii. 3. Neither is
         sometimes used colloquially at the end of a clause to
         enforce a foregoing negative (nor, not, no). "He is
         very tall, but not too tall neither." --Addison. " `I
         care not for his thrust' `No, nor I neither.'" --Shak.
         [1913 Webster]

   Not so neither, by no means. [Obs.] --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

neither
    adj 1: not either; not one or the other