idiopathy

English

From idio- +‎ -pathy. First appears c. 1634, in the publications of Philiatreus (fl. 1630).

idiopathy (plural idiopathies)

(pathology) A disease or condition arising spontaneously or having no known cause.
- 1970, D. V. Salcedo, M. G. Mujica, “A Study of Sterilized Women in the Urban Communities of the Western Area of Santiago, 1963-1966”, in The Journal of Sex Research, volume 6, number 1, page 42:
  The sterilization that was first conceived as a recourse of limited medical reach came to be considered an efficient eugenical procedure that could prevent descendents^[sic] with hereditary and transmissible disorders, such as mental deficiency, epilepsy, idiopathies, etc.

a disease having no known cause