lasting a very short time; short-lived; transitory

the ephemeral joys of childhood.

lasting but one day

an ephemeral flower.

anything short-lived, as certain insects.

adjective

enduring , eternal , everlasting , interminable , lasting , long , permanent , perpetual

adjective

brief , episodic , evanescent , fleeting , flitting , fugacious , fugitive , impermanent , short , short-lived , temporary , transient , transitory , unenduring , volatile , fleet , momentary , passing , temporal , vague