adjective
cadaverous
kuh-DAV-er-uhs/kəˈdævərəs/
So pale and thin as to resemble a dead body.
The woman's hollow cheeks and ashen pallor give her a cadaverous appearance.

Etymology
The pieces mean “corpse-like.” Applied to a living person, cadaverous describes pallor and thinness so extreme that the person resembles a dead body.
In context
much the appearance of death masks when we had taken our places at the little table near the great gas ring I inquired what they were they do look rather cadaverous don't they
More examples
- His cadaverous cheeks made the character look gravely ill.
- A cadaverous figure emerged from the shadows in the story.
- The portrait emphasized her hollow eyes and cadaverous pallor.
Forms
cadaverous
Similar words
- gaunt
- Extremely thin, while cadaverous also suggests deathlike pallor.