DIABOLICAL (adj)

DIABOLICAL(adj): Something that is extremely evil or cruel

Synonyms– poor, dreadful, awful, terrible, frightful, disgraceful

Antonyms– Angelic, Benevolent, Good, Kind, Virtuous, Moral, Righteous, Saintly, Honorable, Pure

Sentence usage– The prank he played on his friend was diabolical and made everyone upset.

Phrase/Idiom–  Heart of stone, a person who is unfeeling, cruel, or merciless.