hideous

Etymology

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.

adj

1. Extremely or shockingly ugly.
2. Having a very unpleasant or frightening sound
3. Hateful; shocking.
4. Morally offensive; shocking; detestable.
   when the wind is shrieking, and the men are yelling, and every plank thunders with trampling feet right over Jonah’s head; in all this raging tumult, Jonah sleeps his hideous sleep. 1851, Herman Melville, Moby Dick, Chapter 9