a falling out of the hair.
Origin of psilosis
1835–45; < New Latin < Greek psī́lōsis literally, a stripping bare, equivalent to psīlō-, variant stem of psīloûn to strip (derivative of psīlós bare, smooth) + -sis -sis
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
"loss of hair through disease," 1837, medical Latin, from Greek psilosis "a stripping of hair," from psiloun "to strip of hair," from psilos "bare" (see psilo-).
Online Etymology Dictionary, © 2010 Douglas Harper