pallor

n. paleness, colorlessness, wanness

Pallor is a reduced amount of oxyhemoglobin in skin or mucous membrane, a pale color which can be caused by illness, emotional shock or stress, avoiding excessive exposure to sunlight, anaemia or genetics. It is more evident on the face and palms. It can develop suddenly or gradually, depending on the cause.
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Pallor /pal·lor/ paleness, as of the skin. pal·lor n. Paleness, as of the skin. pallor, n paleness; absence of skin coloration. [more]Pallor - Community and Resources

Noun
1. unnatural lack of color in the skin (as from bruising or sickness or emotional distress)
(synonym) lividness, lividity, luridness, paleness, pallidness, wanness, achromasia
(hypernym) complexion, skin color, skin colour
(derivation) pale, blanch, blench

(a.)
Paleness; want of color; pallidity; as, pallor of the complexion.