The Collaborative International Dictionary of English v.0.48:

Cohere \Co*here"\, v. i. [imp. & p. p. Cohered; p. pr. & vb.
   n. Cohering.] [L. cohaerere, cohaesum; co- + haerere to
   stick, adhere. See Aghast, a.]
   1. To stick together; to cleave; to be united; to hold fast,
      as parts of the same mass.
      [1913 Webster]

            Neither knows he . . . how the solid parts of the
            body are united or cohere together.   --Locke.
      [1913 Webster]

   2. To be united or connected together in subordination to one
      purpose; to follow naturally and logically, as the parts
      of a discourse, or as arguments in a train of reasoning;
      to be logically consistent.
      [1913 Webster]

            They have been inserted where they best seemed to
            cohere.                               --Burke.
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   3. To suit; to agree; to fit. [Obs.]
      [1913 Webster]

            Had time cohered with place, or place with wishing.
                                                  --Shak.

   Syn: To cleave; unite; adhere; stick; suit; agree; fit; be
        consistent.
        [1913 Webster] Coherence

WordNet (r) 3.0 (2006):

cohere
    v 1: come or be in close contact with; stick or hold together
         and resist separation; "The dress clings to her body"; "The
         label stuck to the box"; "The sushi rice grains cohere"
         [syn: cling, cleave, adhere, stick, cohere]
    2: cause to form a united, orderly, and aesthetically consistent
       whole; "Religion can cohere social groups"
    3: have internal elements or parts logically connected so that
       aesthetic consistency results; "the principles by which
       societies cohere"