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The word ugliness was first recorded in the late 14th century. It comes from the word ugly and the suffix -ness. Ugly appeared in the mid 13th century from an Old Norse word uggligr (“dreadful, fearful”), which itself is from uggr (“fear, apprehension, dread” (perhaps related to agg “strife, hate”)) + –ligr (“-like”).

Ugly is actually an unusual word when compared with other languages because it was formed from the root “fear/dread” rather than the root “ill-shaped”, which is more common among Indo-European words.

[1] Origin and meaning of ugly by Online Etymology Dictionary