しんしん

adverb taking the 'to' particle, taru-adjective

falling heavily (rain, snow)

Describes rain or snow falling steadily and heavily, often with a quiet, persistent quality. Used adverbially with と or as a literary adjective.

• 雪ゆきがしんしんと降ふり積つもる。

  The snow falls heavily and piles up.

• 雨あめがしんしんと降ふり続つづいている。

  The rain continues to fall steadily.