noun ダウンロード 🔗共有 珪藻 Any of a group of minute unicellular algae having a siliceous covering of great delicacy, now categorized as class Diatomophyceae or division Bacillariophyta. Examples : "Microscopic diatoms in the ocean produce a large portion of the Earth's oxygen. " 海中の微小な珪藻は、地球の酸素の大部分を生成します。 organism biology microorganism plant nature environment ecology science AIとチャット語彙ゲーム読解練習