continuing or enduring forever; everlasting.

lasting an indefinitely long time

perpetual snow.

continuing or continued without intermission or interruption; ceaseless

a perpetual stream of visitors all day.

blooming almost continuously throughout the season or the year.

a hybrid rose that is perpetual.

a perennial plant.

adjective

brief , ephemeral , fleeting , momentary , temporary , transient

adjective

abiding , ceaseless , constant , continued , continuous , endless , enduring , eternal , everlasting , going on , immortal , imperishable , incessant , infinite , interminable , intermittent , never-ceasing , never-ending , perdurable , perennial , permanent , persistent , recurrent , recurring , reoccurring , repeated , repeating , repetitious , returning , sempiternal , unceasing , unchanging , undying , unending , unfailing , uninterrupted , unremitting , without end , amaranthine , world without end , around-the-clock , nonstop , ongoing , relentless , round-the-clock , timeless , continual , ever