The Collaborative International Dictionary of English v.0.48:

Fulgurant \Ful"gu*rant\a. [L. fulgurans, p. pr. of fulgurare.]
   Lightening. [R.] --Dr. H. More.
   [1913 Webster]

WordNet (r) 3.0 (2006):

fulgurant
    adj 1: amazingly impressive; suggestive of the flashing of
           lightning; "the skater's dazzling virtuosic leaps";
           "these great best canvases still look as astonishing and
           as invitingly new as they did...when...his fulgurant
           popularity was in full growth"- Janet Flanner;
           "adventures related...in a style both vivid and
           fulgurous"- Idwal Jones [syn: dazzling, eye-popping,
           fulgurant, fulgurous]