Lasting for a markedly brief time: "There remain some truths too ephemeral to be captured in the cold pages of a court transcript” ( Irving R. Kaufman).
Living or lasting only for a day, as certain plants or insects do.
A markedly short-lived thing.
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.