Deserving of or able to be hated; something that causes people to feel dislike or anger toward it.
From Old English hatian (to hate) plus the suffix -able (capable of being). The combination literally means 'capable of being hated' and has been used since at least the 1500s.
Interestingly, 'hatable' is actually harder to prove than 'hateful'—you can say something is hateful (it provokes hate), but hatable means it deserves to be hated, which is a much tougher moral judgment!
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