The quality or state of being cruel; the tendency to inflict pain or suffering without mercy.
From 'cruel' (Latin 'crudelis') with the suffix '-ness', a productive Old English suffix that converts adjectives to abstract nouns representing the quality expressed by the adjective.
The word 'cruelty' exists, but 'cruelness' is technically more grammatically correct—it's the actual quality itself, while 'cruelty' historically referred to specific cruel acts.
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