The Collaborative International Dictionary of English v.0.48:

Disputatious \Dis`pu*ta"tious\, a.
   Inclined to dispute; apt to civil or controvert;
   characterized by dispute; as, a disputatious person or
   temper.
   [1913 Webster]

         The Christian doctrine of a future life was no
         recommendation of the new religion to the wits and
         philosophers of that disputations period.
                                                  --Buckminster.
   -- Dis`pu*ta"tious*ly, adv. -- Dis`pu*ta"tious*ness, n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

disputatious
    adj 1: inclined or showing an inclination to dispute or
           disagree, even to engage in law suits; "a style described
           as abrasive and contentious"; "a disputatious lawyer"; "a
           litigious and acrimonious spirit" [syn: contentious,
           combative, disputatious, disputative, litigious]

Moby Thesaurus II by Grady Ward, 1.0:

59 Moby Thesaurus words for "disputatious":
   aggressive, argumental, argumentative, bellicose, belligerent,
   bickering, cat-and-dog, cat-and-doggish, combative, complaining,
   contentious, controversial, dialectic, disputing, dissentient,
   dissenting, divisive, eristic, factional, factious, fractious,
   ill-humored, irascible, irritable, litigious, logomachic,
   noncooperative, objecting, obstructive, on the barricades,
   partisan, pilpulistic, polarizing, polemic, polemical, pro and con,
   proof against, protesting, pugnacious, quarrelsome, rebellious,
   recalcitrant, refractory, reluctant, renitent, repellent,
   resistant, resisting, resistive, retardant, retardative, scrappy,
   shrewish, uncooperative, unsubmissive, unyielding, up in arms,
   withstanding, wrangling