Ætiology /(ē`tĭ*ŏl"ō̇*jy̆)/

Æ·ti·ol·o·gy

Ætiology

n.
  1. The science, doctrine, or demonstration of causes; esp., the investigation of the causes of any disease; the science of the origin and development of things.
  2. The assignment of a cause.
  3. The cause or origin of a disease. Now more commonly written etiology. (Med.)