Source : Webster's Revised Unabridged Dictionary (1913)

Fluster \Flus"ter\, v. t. [imp. & p. p. {Flustered}; p. pr. &
   vb. n. {Flustering}.] [Cf. Icel. flaustra to be flustered,
   flaustr a fluster.]
   To make hot and rosy, as with drinking; to heat; hence, to
   throw into agitation and confusion; to confuse; to muddle.

         His habit or flustering himself daily with claret.
                                                  --Macaulay.

Source : WordNet®

flustered
     adj : thrown into a state of agitated confusion; (`rattled' is an
           informal term) [syn: {hot and bothered(p)}, {perturbed},
            {rattled}]