ephemeral

/əˈfɛ.mə.ɹəl/
noun
1

Something which lasts for a short period of time.

Synonyms: ephemeron

More synonyms: ephemeron
adjective
1

Lasting for a short period of time.

Synonyms: evanescent, fleeting, momentary, short, short-lived, temporary, transitory, volatile

Antonyms: eternal, everlasting, permanent, timeless

2

Existing for only one day, as with some flowers, insects, and diseases.

3

(of a body of water) Usually dry, but filling with water for brief periods during and after precipitation.

More synonyms: evanescent, fleeting, momentary, short, short-lived, temporary, transitory, volatile
Source: https://en.wiktionary.org/wiki/ephemeral

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