What does "ephemeral" mean?

Ephemeral: Short-lived; existing or continuing for a short time only. "Ephemeral popularity." V. Knox. Sentences not of ephemeral, but of eternal, efficacy. Sir J. Stephen. Ephemeral fly (Zoöl.), one of a group of neuropterous insects, belonging to the genus Ephemera and many allied genera, which live in the adult or winged state only for a short time. The larvæ are aquatic; -- called also day fly and May fly.

Additional senses

  1. 2.Anything lasting but a day, or a brief time; an ephemeral plant, insect, etc.

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