malevolent

他露出了邪恶的笑容，显然心怀不轨。

He gave a ___malevolent smile, clearly intending harm.

老宅里的恶灵似乎一夜比一夜更加强大。

The ___malevolent spirit in the old mansion seemed to grow stronger each passing night.

这个恶意的谣言在几小时内就传遍了办公室，意在破坏她的晋升。

The ___malevolent rumor spread through the office within hours, designed to sabotage her promotion.