Chinese

Noun

暴雨

1. cloudburst, sudden heavy rainstorm

Japanese

Etymology 1

Compound of 群 ‎(mura, “gather”) +‎ 雨 ‎(same, “rain”). Literally rain that falls when clouds gather together.

Noun

暴雨 ‎(hiragana むらさめ, romaji murasame)

1. a sudden rain
   • 931–938, Wamyō Ruijushō, book 1, page 26:

     暴雨 楊氏漢語抄云、白雨、和名无良佐女 [...]

Alternative forms

• 群雨
• 叢雨
• 村雨

Etymology 2

Compound of 速 ‎(haya, “fast”) +‎ 雨 ‎(same, “rain”).

Noun

暴雨 ‎(hiragana はやさめ, romaji hayasame)

1. a sudden and strong rain

Alternative forms

• 速雨

References

• Minamoto, Shitagō; Kyōto Daigaku Bungakubu Kokugogaku Kokubungaku Kenkyūshitu (931–938) Shohon Shūsei Wamyō Ruijushō: Honbunhen (in Japanese), Kyōto: Rinsen, ISBN 978-4-653-00507-0, published 1968.