Literally meaning: “old or gray state or whitening”
Origin: Anc Greek
πολιός/polios(=old, gray, venerable) >παλαιός/palaios(=old, as in Paleontology)
+(-ωσις/(-osis)(=suffix denoting process or state)
Poliosis is a localized patch of white hair caused by decrease in melanin amount in head hair, eyebrows, or eyelashes. Poliosis occurs in several hereditary syndromes (as Marfan's syndrome and tuberous sclerosis) but may be caused also by others factors as inflammation, irradiation, or infection.