Source : Webster's Revised Unabridged Dictionary (1913)

Highflying \High"fly`ing\, a.
   Extravagant in opinions or ambition. ``Highflying, arbitrary
   kings.'' --Dryden.

Source : WordNet®

highflying
     adj 1: moving upward or along at a considerable height; "some
            highflying fighter pilot fired a cannon shell into it"
            [syn: {highflying(a)}]
     2: extravagant or ambitious or extreme in aims or opinions;
        "they did not understand what had happend at the once
        highflying company" [syn: {highflying(a)}]