hideous
adj.adj. extremely ugly or unpleasant to look at. You can also use it to describe something that is morally shocking or very bad.
adj. extremely unpleasant or offensive to the senses, especially the sight; aesthetically or morally repulsive.
The old wallpaper was a hideous shade of green.
The architect's new design was widely criticized as a hideous addition to the historic skyline.
The witness provided a hideous account of the events, detailing a level of cruelty that left the entire courtroom in a state of stunned silence.
From Middle English hidous, from Anglo-Norman hidous, from Old French hideus, hydus (“that which inspires terror”), from earlier hisdos, from Old French hisda (“horror, fear”), of uncertain and disputed origin. Probably from Proto-West Germanic agisiþu (“horror, terror”), from Proto-West Germanic agisōn (“to frighten, terrorise”), from Proto-Germanic agaz (“terror, fear”), from Proto-Indo-European h₂egʰ- (“to frighten”). Cognate with Old High German egisa, egidī (“horror”), Old English egesa (“fear, dread”), Gothic 𐌰𐌲𐌹𐍃 (agis, “fear, terror”). Alternative etymology cites possible derivation from Latin hispidosus (“rugged”), from hispidus (“rough, bristly”), yet the semantic evolution is less plausible.
Often used to describe colors, buildings, or crimes; can be used both attributively and predicatively.