Chinese

Noun

蜉蝣

1. mayfly

Japanese

蜉蝣 (kagerō, fuyū): a mayfly.

Etymology 1

Change in meaning from 陽炎 ‎(kagerō, “heat haze, heat shimmer”), from the way that the insects fly in swarms that visually resemble heat haze.^[1]

Pronunciation

• (Irregular reading)
• (Tokyo) かげ​ろう [kàgéꜜròò] (Nakadaka - [2])^[2][3]
• (Tokyo) かげろう [kàgéróó] (Heiban - [0])^[2][3]
• IPA^(key): [ka̠ɡ̃e̞ɺ̠o̞ː]

Alternative forms

• 蜻蛉 (obsolete)

Noun

蜉蝣 ‎(hiragana かげろう, katakana カゲロウ, romaji kagerō, historical hiragana かげろふ)

1. mayfly
2. (obsolete) dragonfly

Usage notes

As with many terms that name organisms, this term is often spelled in katakana in biological contexts, as カゲロウ.

Idioms

Etymology 2

Change in meaning from 陽炎 ‎(kagirō, “heat haze, heat shimmer”), from the way that the insects fly in swarms that visually resemble heat haze.^[1]

Obsolete reading.

Alternative forms

• 蜻蛉 (obsolete)

Noun

蜉蝣 ‎(hiragana かぎろう, romaji kagirō, historical hiragana かぎろふ)

1. (obsolete) dragonfly

Etymology 3

From Middle Chinese compound 蜉蝣 ‎(bjuw yuw?, literally “mayfly + mayfly”). Compare modern Mandarin 蜉蝣 (fúyóu, “mayfly”).

Pronunciation

• On'yomi
• (Tokyo) ふゆう [fùyúú] (Heiban - [0])^[2]
• (Tokyo) ふ​ゆう [fúꜜyùù] (Atamadaka - [1])^[2]
• IPA^(key): [ɸɯᵝjɯᵝː]

Noun

蜉蝣 ‎(hiragana ふゆう, romaji fuyū, historical hiragana ふいう)

1. mayfly
2. ephemerality (by extension from the way that mayflies are born and die within a day)

Idioms

References

1. 1 2 1988, 国語大辞典（新装版） (Kokugo Dai Jiten, Revised Edition) (in Japanese), Tōkyō: Shogakukan
2. 1 2 3 4 2006, 大辞林 (Daijirin), Third Edition (in Japanese), Tōkyō: Sanseidō, ISBN 4-385-13905-9
3. 1 2 1998, NHK日本語発音アクセント辞典 (NHK Japanese Pronunciation Accent Dictionary) (in Japanese), Tōkyō: NHK, ISBN 978-4-14-011112-3