The Collaborative International Dictionary of English v.0.48:

jingoistic \jin`go*ist"ic\, a.
   1. fanatically and bellicosely patriotic; aggressively
      chauvinistic; belligerent in international relations.

   Syn: chauvinistic, flag-waving(prenominal), nationalistic,
        superpatriotic.
        [PJC]

   2. Given to expressing partisan sentiments in slogans,
      especially belligerently patriotic views.
      [PJC]

WordNet (r) 3.0 (2006):

jingoistic
    adj 1: fanatically patriotic [syn: chauvinistic, flag-
           waving(a), jingoistic, nationalistic,
           ultranationalistic, superpatriotic]