high-flier

from The Collaborative International Dictionary of English v.0.48

Highflier \High"fli`er\, n.
   1. One who is extravagant in pretensions, opinions, or
      manners; one who is highfaluting. --Swift.
      [1913 Webster +PJC]

   2. a person of great ability and ambition. [WordNet sense 1]

   Syn: highflyer.
        [WordNet 1.5]