Morgellons

Etymology
Coined in 2002 by Mary Leitao after a description of an illness in 's  (c. 1656, pub. 1690), "that endemial distemper of children in Languedoc, called the morgellons, wherein they critically break out with harsh hairs on their backs", apparently a corruption of Masquelons, from.

Noun

 * 1)  An unproven skin disorder, usually thought to be delusional parasitosis, characterized by skin lesions in which fibers are found.
 * 2)  A disease causing hairs to grow on the backs of children.