ephemeralPronunciation: /ɪˈfɛm(ə)r(ə)l, -ˈfiːm-/Translate ephemeral | into German | into Italian Definition of ephemeral adjective lasting for a very short time: fashions are ephemeral: new ones regularly drive out the old works of more than ephemeral interest (chiefly of plants) having a very short life cycle: chickweed is an ephemeral weed, producing several generations in one season noun an ephemeral plant: ephemerals avoid the periods of drought as seedsDerivatives ephemeralityPronunciation: /-ˈralɪti/ noun ephemerally adverb Origin: late 16th century: from Greek ephēmeros (see ephemera) + -alephemeral in other Oxford dictionaries Definition of ephemeral in the US English dictionary