1.
1. 短命之物：ephemeris 星历表 | ephemeron 短命之物 | Ephesian 以弗所的
2. 蜉蝣：dormouse 睡鼠 | ephemeron 蜉蝣 | ewe 母羊
3. ephemeron
3. 生命极短促之物/蜉蝣：ephemeris /位置推算历/ | ephemeron /生命极短促之物/蜉蝣/ | ephippium /鞍状壳/垂体窝/
danci.edu.pub
noun
1. anything short-lived, as an insect that lives only for a day in its winged form
Synonym: ephemeral