The Collaborative International Dictionary of English v.0.48:

Both \Both\ (b[=o]th), a. or pron. [OE. bothe, ba[thorn]e, fr.
   Icel. b[=a][eth]ir; akin to Dan. baade, Sw. b[*a]da, Goth.
   baj[=o][thorn]s, OHG. beid[=e], b[=e]d[=e], G. & D. beide,
   also AS. begen, b[=a], b[=u], Goth. bai, and Gr. 'a`mfw, L.
   ambo, Lith. ab[`a], OSlav. oba, Skr. ubha. [root]310. Cf.
   Amb-.]
   The one and the other; the two; the pair, without exception
   of either.
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   Note: It is generally used adjectively with nouns; as, both
         horses ran away; but with pronouns, and often with
         nous, it is used substantively, and followed by of.
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   Note: It frequently stands as a pronoun.
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               She alone is heir to both of us.   --Shak.
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               Abraham took sheep and oxen, and gave them unto
               Abimelech; and both of them made a covenant.
                                                  --Gen. xxi.
                                                  27.
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               He will not bear the loss of his rank, because he
               can bear the loss of his estate; but he will bear
               both, because he is prepared for both.
                                                  --Bolingbroke.
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   Note: It is often used in apposition with nouns or pronouns.
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               Thy weal and woe are both of them extremes.
                                                  --Shak.
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               This said, they both betook them several ways.
                                                  --Milton.
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   Note: Both now always precedes any other attributive words;
         as, both their armies; both our eyes.
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   Note: Both of is used before pronouns in the objective case;
         as, both of us, them, whom, etc.; but before
         substantives its used is colloquial, both (without of)
         being the preferred form; as, both the brothers.
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The Collaborative International Dictionary of English v.0.48:

Both \Both\, conj.
   As well; not only; equally.
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   Note: Both precedes the first of two co["o]rdinate words or
         phrases, and is followed by and before the other, both
         . . . and . . .; as well the one as the other; not only
         this, but also that; equally the former and the latter.
         It is also sometimes followed by more than two
         co["o]rdinate words, connected by and expressed or
         understood.
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               To judge both quick and dead.      --Milton.
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               A masterpiece both for argument and style.
                                                  --Goldsmith.
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               To whom bothe heven and erthe and see is sene.
                                                  --Chaucer.
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               Both mongrel, puppy, whelp, and hound.
                                                  --Goldsmith.
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               He prayeth well who loveth well
               Both man and bird and beast.       --Coleridge.
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WordNet (r) 3.0 (2006):

both
    adj 1: (used with count nouns) two considered together; the two;
           "both girls are pretty"

Moby Thesaurus II by Grady Ward, 1.0:

25 Moby Thesaurus words for "both":
   a deux, brace, couple, couplet, distich, double harness, doublet,
   duad, duet, duo, dyad, either, for two, match, mates, pair,
   set of two, span, team, tete-a-tete, the two, twain, two, twosome,
   yoke