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germ; germs; bacteria; bug
something dirty or harmful; vermin
手を洗わないと黴菌が体に入るよ。
If you don't wash your hands, germs will get into your body.
黴菌の繁殖を防ぐために冷蔵庫に入れた。
I put it in the refrigerator to prevent bacteria from multiplying.
まるで黴菌のように周囲から避けられている。
He is shunned by everyone around him as if he were a plague.