noun, plural e·phem·er·as, e·phem·er·ae [ih-fem-uh-ree] /ɪˈfɛm əˌri/ for 2.

a plural of ephemeron.
an ephemerid.

Origin of ephemera

1670–80; < Greek ephḗmera, neuter plural of ephḗmeros, taken as singular; see ephemeral


[ih-fem-uh-ron, -er-uh n]

noun, plural e·phem·er·a [ih-fem-er-uh] /ɪˈfɛm ər ə/, e·phem·er·ons.

anything short-lived or ephemeral.
ephemera, items designed to be useful or important for only a short time, especially pamphlets, notices, tickets, etc.

Origin of ephemeron

1570–80; < Greek ephḗmeron short-lived insect, noun use of neuter of ephḗmeros; see ephemeral
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for ephemera

Contemporary Examples of ephemera

  • The paintings, ephemera, wall texts, and audio tour construct a story of an obsessive, gifted genius who lived for love and art.

    The Daily Beast logo
    Art's Obsessive Genius

    Paul Laster

    May 20, 2009

Historical Examples of ephemera

  • The Ephemera is the fly which is born but to die, living a single hour of love.

    The Insect

    Jules Michelet

  • The Ephemera and probably the other Neuroptera have abdominal spiracles.

  • The cut represents the circulation in the vessels of the larva of an Ephemera.

  • That was it—as indifferent as we could be to the struggle of an ephemera; and as mildly curious.

  • Near the water side I caught an Ephemera, of which I made a drawing and description.

    Lachesis Lapponica

    Carl von Linn

British Dictionary definitions for ephemera


noun plural -eras or -erae (-əˌriː)

a mayfly, esp one of the genus Ephemera
something transitory or short-lived
(functioning as plural) a class of collectable items not originally intended to last for more than a short time, such as tickets, posters, postcards, or labels
a plural of ephemeron

Word Origin for ephemera

C16; see ephemeral


noun plural -era (-ərə) or -erons

(usually plural) something transitory or short-lived

Word Origin for ephemeron

C16: see ephemeral
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for ephemera

late 14c., originally a medical term, from Medieval Latin ephemera (febris) "(fever) lasting a day," from fem. of ephemerus, from Greek ephemeros "lasting only one day, short-lived," from epi "on" (see epi-) + hemerai, dative of hemera "day," from PIE *amer- "day."

Sense extended 17c. to short-lived insects and flowers; general sense of "thing of transitory existence" is first attested 1751. Cf. Greek ephemeroi "men," literally "creatures of a day."



1620s, from Greek (zoon) ephemeron, neuter of ephemeros (see ephemera). Figurative use by 1771.

Online Etymology Dictionary, © 2010 Douglas Harper