The Collaborative International Dictionary of English v.0.48:

Fustigate \Fus"ti*gate\, v. t. [L. fustigare, fr. fustis stick.
   See 1st Fust.]
   To cudgel. [R.] --Bailey.
   [1913 Webster]

WordNet (r) 3.0 (2006):

fustigate
    v 1: strike with a cudgel [syn: cudgel, fustigate]

Moby Thesaurus II by Grady Ward, 1.0:

54 Moby Thesaurus words for "fustigate":
   assail, attack, baste, bastinado, beat, belabor, belt, birch,
   blister, buffet, cane, castigate, club, cowhide, cudgel, cut, drub,
   excoriate, flagellate, flail, flay, flog, give a whipping,
   give the stick, horsewhip, knout, lace, lash, lay on, pistol-whip,
   pommel, pummel, rawhide, roast, scarify, scathe, scorch, scourge,
   skin alive, slash, smite, spank, strap, stripe, swinge, switch,
   thrash, thump, trounce, truncheon, wallop, whale, whip, whop