Heinous

google

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late Middle English: from Old French haineus, from hair ‘to hate’, of Germanic origin.

wiktionary

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From Middle English hainous, from Old French haïneus (compare French haineux) from haïr(“to hate”), hadir(“to hate”) (compare Old French enhadir(“to become filled with hate”)), from Frankish *hattjan(“to hate”)

etymonline

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heinous (adj.)

late 14c., "hateful, odious, atrocious," from Old French hainos "inconvenient, awkward; hateful, unpleasant; odious" (12c., Modern French haineux), from haine "hatred, hate," from hair "to hate," from Frankish, from Proto-Germanic *hatjan, from PIE *kad- "sorrow, hatred" (see hate (v.)). Related: Heinously; heinousness.