The Collaborative International Dictionary of English v.0.48:

Divisive \Di*vi"sive\, a. [Cf. F. divisif.]
   1. Indicating division or distribution. --Mede.
      [1913 Webster]

   2. Creating, or tending to create, division, separation, or
      difference.
      [1913 Webster]

            It [culture] is after all a dainty and divisive
            quality, and can not reach to the depths of
            humanity.                             --J. C.
                                                  Shairp.
      -- Di*vi"sive*ly, adv. -- Di*vi"sive*ness, n.
      --Carlyle.
      [1913 Webster]

WordNet (r) 3.0 (2006):

divisive
    adj 1: dissenting (especially dissenting with the majority
           opinion) [syn: dissentious, divisive, factious]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "divisive":
   aggressive, bellicose, belligerent, bickering, combative,
   disputatious, eristic, factional, factious, irascible, irritable,
   litigious, partisan, polarizing, polemic, pugnacious, quarrelsome,
   shrewish, wrangling