forward and back (adjective) to and fro: back and forth
Sinonime: cursory, ephemeral, evanescent, fading, flash in the pan, flitting,
flying, fugacious, fugitive, impermanent, meteoric, momentary, passing, short, short-lived,
sudden, temporary, transitory, vanishing, volatile
Antonime: constant,
continual,
endless, enduring, lasting,
lengthy, long, long-lived, permanent, perpetual