The quality or state of being full of hatred; the characteristic of being extremely malicious or deserving to be hated.
Hateful (hate + -ful) + -ness noun suffix (Old English -nes). The -ness suffix converts adjectives into abstract nouns describing qualities or states.
Neuroscience research suggests that harboring hatefulness actually damages the person feeling it more than the target—chronic hatred elevates stress hormones and increases disease risk!
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