sallow

Sallow means unhealthy in appearance––often yellow in color––and is almost invariably used to describe someone's complexion. His smile was as engaging as ever, but from his sallow complexion, I knew he was sick.

Usually we say that when someone is sick they turn "green." You could also say their skin takes on a sallow look, and you'd mean the same thing. Sallow also describes the way someone looks if they have lost blood or are pale from fever.

Primary Meanings of sallow

1.
adjv
unhealthy looking
cause to become sallow
2.
n
any of several Old World shrubby broad-leaved willows having large catkins; some are important sources for tanbark and charcoal
Full Definitions of sallow
1

adj unhealthy looking

Synonyms:
sickly
unhealthy
not in or exhibiting good health in body or mind

v cause to become sallow

“The illness has sallowed her face”
Type of:
discolor
cause to lose or change color
2

n any of several Old World shrubby broad-leaved willows having large catkins; some are important sources for tanbark and charcoal

Types:
Salix caprea, florist's willow, goat willow, pussy willow
much-branched Old World willow having large catkins and relatively large broad leaves
Type of:
willow, willow tree
any of numerous deciduous trees and shrubs of the genus Salix