cruel

fierce, ferocious, barbarous, savage, cruel mean showing fury or malignity in looks or actions. fierce applies to humans and animals that inspire terror because of their wild and menacing aspect or fury in attack.

• • fierce warriors

ferocious implies extreme fierceness and unrestrained violence and brutality.

• • a ferocious dog

barbarous implies a ferocity or mercilessness regarded as unworthy of civilized people.

• • barbarous treatment of prisoners

savage implies the absence of inhibitions restraining civilized people filled with rage, lust, or other violent passion.

• • a savage criminal

cruel implies indifference to suffering and even positive pleasure in inflicting it.

• • the cruel jokes of schoolboys