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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The Collaborative International Dictionary of English v.0.48:

Combine \Com*bine"\, v. i.
   1. To form a union; to agree; to coalesce; to confederate.
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            You with your foes combine,
            And seem your own destruction to design --Dryden.
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            So sweet did harp and voice combine.  --Sir W.
                                                  Scott.
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   2. To unite by affinity or natural attraction; as, two
      substances, which will not combine of themselves, may be
      made to combine by the intervention of a third.
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   3. (Card Playing) In the game of casino, to play a card which
      will take two or more cards whose aggregate number of pips
      equals those of the card played.
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   Combining weight (Chem.), that proportional weight, usually
      referred to hydrogen as a standard, and for each element
      fixed and exact, by which an element unites with another
      to form a distinct compound. The combining weights either
      are identical with, or are multiples or submultiples of,
      the atomic weight. See Atomic weight, under Atomic, a.
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WordNet (r) 3.0 (2006):

combine
    n 1: harvester that heads and threshes and cleans grain while
         moving across the field
    2: a consortium of independent organizations formed to limit
       competition by controlling the production and distribution of
       a product or service; "they set up the trust in the hope of
       gaining a monopoly" [syn: trust, corporate trust,
       combine, cartel]
    3: an occurrence that results in things being united [syn:
       combining, combine]
    v 1: have or possess in combination; "she unites charm with a
         good business sense" [syn: unite, combine]
    2: put or add together; "combine resources" [syn: compound,
       combine]
    3: combine so as to form a whole; mix; "compound the
       ingredients" [syn: compound, combine]
    4: add together from different sources; "combine resources"
    5: join for a common purpose or in a common action; "These
       forces combined with others"
    6: gather in a mass, sum, or whole [syn: aggregate, combine]
    7: mix together different elements; "The colors blend well"
       [syn: blend, flux, mix, conflate, commingle,
       immix, fuse, coalesce, meld, combine, merge]