also: くもつぶ
noun
cloud droplet
Technical term in meteorology for the tiny water droplets that form clouds.
雲粒は直径が約0.01ミリメートルです。
Cloud droplets are about 0.01 millimeters in diameter.
気象学では、雲粒の成長過程を詳しく研究します。
In meteorology, the growth process of cloud droplets is studied in detail.
Compound of 雲 (cloud) and 粒 (grain/droplet). The reading うんりゅう uses the on'yomi of both characters, while くもつぶ uses the kun'yomi.