The state or quality of being extremely dislikable, hateful, or worthy of strong disapproval.
From 'detestable' (worthy of hatred) plus '-ness' to form a noun. Alternative form of 'detestability' from Latin 'detestari' (to curse).
While 'detestability' is the fancy academic version, 'detestableness' sounds more natural in everyday speech—yet both mean exactly the same thing!
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