malignancy

The malignancy spread rapidly throughout the body.

悪性腫瘍は体中に急速に広がった。

There was a malignancy in his tone that made everyone uncomfortable.

彼の口調には悪意があり、皆を不快にさせた。

The malignancy of the pollution was evident in the declining health of the residents.

汚染の有害性は住民の健康の悪化に明らかだった。