Synonyms for Cruel (same or very similar meaning)
WordNet sense 1 ((of weapons or instruments) causing suffering and pain):
brutal
WordNet sense 2 ((of persons or their actions) able or disposed to inflict pain or suffering):
barbarous, fell, roughshod, savage, vicious
WordNet sense 3 (lacking and reflecting lack of pity or compassion):
inhumane
From the ODE community, based on WordNet
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