(ˈ)fyü|gāshəs adjective
Etymology: Latin fugac-, fugax swift, fleeting (from fugere to run away) + English -ious — more at fugitive
1.
a. : of an unsubstantial nature : lasting a short time : evanescent
the painter's fame is based on the most fugacious of substances — public favor — Frederic Taubes
b. also fugaceous : falling off or disappearing before the usual time — used chiefly of plant parts other than floral organs (as stipules or moss calyptras); opposed to persistent ; compare caducous , deciduous
2. : not fixed in a certain place : wandering
unlike other minerals … oil and gas are … fugacious — Robert Kratovil