Douglas Harper's Etymology Dictionary
hideosity
"a very ugly thing," 1807, from hideous on model of monstrosity, etc.
Wiktionary
hideosity
n. 1 (context uncountable English) The state or condition of being hideous; extreme ugliness. 2 (context countable English) Something hideous.
Usage examples of "hideosity".
They had seen an endless procession of hideosities in their westward journey through the peninsula.
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