The Collaborative International Dictionary of English v.0.48:

Combine \Com*bine"\ (k[o^]m*b[imac]n"), v. t. [imp. & p. p.
   Combined (k[o^]m*b[imac]nd"); p. pr. & vb. n. Combining.]
   [LL. combinare, combinatum; L. com- + binus, pl. bini, two
   and two, double: cf. F. combiner. See Binary.]
   1. To unite or join; to link closely together; to bring into
      harmonious union; to cause or unite so as to form a
      homogeneous substance, as by chemical union.
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            So fitly them in pairs thou hast combined. --Milton.
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            Friendship is the cement which really combines
            mankind.                              --Dr. H. More.
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            And all combined, save what thou must combine
            By holy marriage.                     --Shak.
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            Earthly sounds, though sweet and well combined.
                                                  --Cowper.
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   2. To bind; to hold by a moral tie. [Obs.]
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            I am combined by a sacred vow.        --Shak.
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WordNet (r) 3.0 (2006):

combining
    n 1: an occurrence that results in things being united [syn:
         combining, combine]
    2: the act of combining things to form a new whole [syn:
       combination, combining, compounding]