Evanescent

adj. Something that is disappearing, or that only happens for moments; ephemeral

Yes, it sounds like the name of that band…but many people don’t know what the actual word means.

Examples:

Human life, with all its unreal ills and transitory hopes, is as a dream, which departs before the dawn, leaving no trace of its evanescent lines.
— Percy Shelley, Essay on Christianity (1859)

It was a dark world; it was full of preventable disorder, preventable diseases, and preventable pain of harshness and stupid unpremeditated cruelties; but yet, it may be even by virtue of the general darkness, there were moments of a rare and evanescent beauty that seems no longer possible in my experience.
— H. G. Wells, In the Days of the Comet (1906)

He believed that it was for the man of letters to record these epiphanies with extreme care, seeing that they themselves are the most delicate and evanescent of moments.
— James Joyce, Stephen Hero (1944)

Our knowledge of physics only takes us back so far. Before this instant of cosmic time, all the laws of physics or chemistry are as evanescent as rings of smoke.
— Joseph Silk, The Infinite Cosmos (2006)

Etymology: Easier than it sounds: Latin, “ex” (out of) and vanescere, which also forms the word “vanish”