perpetuity, n.All

Perpetuity (n.) is ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠time's imitation of eternity: unable to hold its life all at once, the world keeps it going by marching forward forever.