The story
Either named after Stanley Ellin's book of same name or coined by Charles L. Grant.
Etymology from Wiktionary, CC BY-SA 4.0.
quiet horror
Today it means: A subgenre of horror and psychological horror that doesn't rely on explicit, graphic elements or cheap thrills (e.g. jumpscares, gore, shock tactics etc.); but relies on atmosphere, subtlety, uncanniness and slow-burning tension. Full definition →