ephemeral

UK: /ɪˈfɛmərəl/ US: /ɪˈfɛmərəl/ ,(i fem′ər əl)

WordReference Random House Learner's Dictionary of American English © 2025

e•phem•er•al /ɪˈfɛmərəl/   adj. 

1. lasting a very short time;
   short-lived;
   transitory:
   the ephemeral joys of youth.

WordReference Random House Unabridged Dictionary of American English © 2025

e•phem•er•al  (i fem′ər əl), adj. 

1. lasting a very short time;
   short-lived;
   transitory:
   the ephemeral joys of childhood.
2. lasting but one day:
   an ephemeral flower.

n. 

3. anything short-lived, as certain insects.

• Greek ephé̄mer(os) short-lived, lasting but a day (ep- ep- + hēmér(a) day + -os adjective, adjectival suffix) + -al¹
• 1570–80

e•phem′er•al•ly, adv. 
e•phem′er•al•ness, n. 
Synonyms

• 1. fleeting, evanescent, transient, momentary, brief.

Antonyms

• 1. permanent.

Collins Concise English Dictionary © HarperCollins Publishers::

ephemeral / ɪˈfɛmərəl/ adjective

1. lasting for only a short time; transitory; short-lived: ephemeral pleasure

noun

1. a short-lived organism, such as the mayfly
2. a plant that completes its life cycle in less than one year, usually less than six months

Etymology: 16th Century: from Greek ephēmeros lasting only a day, from hēmera day

eˌphemerˈality, eˈphemeralness noun