The Collaborative International Dictionary of English v.0.48:

Waspish \Wasp"ish\, a.
   1. Resembling a wasp in form; having a slender waist, like a
      wasp.
      [1913 Webster]

   2. Quick to resent a trifling affront; characterized by
      snappishness; irritable; irascible; petulant; snappish.
      [1913 Webster]

            He was naturally a waspish and hot man. --Bp. Hall.
      [1913 Webster]

            Much do I suffer, much, to keep in peace
            This jealous, waspish, wrong-head, rhyming race.
                                                  --Pope.
      [1913 Webster]

   Syn: Snappish; petulant; irritable; irascible; testy;
        peevish; captious.
        [1913 Webster] -- Wasp"ish*ly, adv. --
        Wasp"ish*ness, n.
        [1913 Webster]

WordNet (r) 3.0 (2006):

waspish
    adj 1: very irritable; "bristly exchanges between the White
           House and the press"; "he became prickly and spiteful";
           "witty and waspish about his colleagues" [syn: bristly,
           prickly, splenetic, waspish]

Moby Thesaurus II by Grady Ward, 1.0:

40 Moby Thesaurus words for "waspish":
   bearish, bitchy, cankered, cantankerous, churlish, contrary,
   crabbed, cranky, cross, cross-grained, crotchety, crusty, cussed,
   disagreeable, excitable, feisty, fractious, fretful, huffish,
   huffy, impatient, irascible, irritable, malicious, mean, ornery,
   peevish, perverse, pettish, petulant, querulous, sharp, snappish,
   spiteful, spleeny, splenetic, testy, ugly, vinegarish, vinegary