Source : Webster's Revised Unabridged Dictionary (1913)

Fugacious \Fu*ga"cious\, a. [L. fugax, fugacis, from fugere: cf.
   F. fugace. See {Fugitive}.]
   1. Flying, or disposed to fly; fleeing away; lasting but a
      short time; volatile.

            Much of its possessions is so hid, so fugacious, and
            of so uncertain purchase.             --Jer. Taylor.

   2. (Biol.) Fleeting; lasting but a short time; -- applied
      particularly to organs or parts which are short-lived as
      compared with the life of the individual.

Source : WordNet®

fugacious
     adj : enduring a very short time; "the ephemeral joys of
           childhood"; "a passing fancy"; "youth's transient
           beauty"; "love is transitory but at is eternal";
           "fugacious blossoms" [syn: {ephemeral}, {passing}, {short-lived},
            {transient}, {transitory}]