deleteriously

In a deleterious manner; harmfully.

Japanese Meaning

有害な方法で / 損害を与えるように / 害悪的に

The pollutant affected the river's ecosystem deleteriously, causing fish populations to decline rapidly.

その汚染物質は川の生態系に有害な影響を及ぼし、魚の個体数は急速に減少した。

Sense（1）

In a deleterious manner; harmfully.

more deleteriously

（ comparative ）

most deleteriously

（ superlative ）