Source : Webster's Revised Unabridged Dictionary (1913)

Fluster \Flus"ter\, v. i.
   To be in a heat or bustle; to be agitated and confused.

         The flstering, vainglorious Greeks.      --South.

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.

Fluster \Flus"ter\, n.
   Heat or glow, as from drinking; agitation mingled with
   confusion; disorder.

Source : WordNet®

fluster
     n : a disposition that is confused or nervous and upset [syn: {perturbation}]
     v 1: be flustered; behave in a confused manner
     2: cause to be nervous or upset