Definition of 蜉蝣 (かげろう)

noun
1.
mayfly, ephemeropteran(usually kana)
2.
ephemerality (of human life)(usually kana)
3.
dragonfly, damselfly(archaism, usually kana)(only relevant for かげろう)
Other readings:
ふゆう《蜉蝣》
カゲロウ
Related Kanji
kind of ant, may fly
mayfly