すうすう

adverb, adverb taking the 'to' particle, noun or participle which takes 'suru'

whistling sound of wind through a crack; wheezing

Onomatopoeic word for a soft, continuous hissing or whistling sound, often from wind passing through a narrow gap or from labored breathing. Can be used adverbially with と or as a する-verb.

• 窓まどの隙すき間まから風かぜがすうすうと入はいってくる。

  The wind comes whistling in through the crack in the window.