The Collaborative International Dictionary of English v.0.48:

Spleeny \Spleen"y\, a.
   1. Irritable; peevish; fretful.
      [1913 Webster]

            Spleeny Lutheran, and not wholesome to
            Our cause.                            --Shak.
      [1913 Webster]

   2. Affected with nervous complaints; melancholy.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "spleeny":
   bearish, bitchy, cankered, cantankerous, churlish, crabbed, cranky,
   cross, cross-grained, crusty, cussed, disagreeable, excitable,
   feisty, fractious, huffish, huffy, irascible, irritable, mean,
   ornery, perverse, snappish, spiteful, splenetic, testy, ugly,
   waspish