eldritch
adjective·/ˈɛl.drɪtʃ/
Weirdly uncanny, eerie in a way that feels old, inhuman, and slightly wrong. Familiar shapes become suspect when an alien undertone enters them. Something older than fear, and less interested in us.
An eldritch glow seeped from the marsh at dusk, and even the birds kept their distance.
Etymology
From Scots eldritch “strange, eerie,” probably related to an older sense of “other” or “foreign.” The word carries the atmosphere of borderlands—places where the known world thins and the “elsewhere” presses close.
Related Words
uncannynear-synonym; less archaic in flavor
chthonianof underworld depths; a darker mythic neighbor
weirdsharing ancestry in fate and strangeness, but broader
numinousawe-filled presence; less sinister than eldritch