"Etiology (/i\u02D0ti\u02C8\u0252l\u0259d\u0292i/; alternatively aetiology or \u00E6tiology) is the study of causation, or origination. The word is derived from the Greek \u03B1\u1F30\u03C4\u03B9\u03BF\u03BB\u03BF\u03B3\u03AF\u03B1, aitiologia, \"giving a reason for\" (\u03B1\u1F30\u03C4\u03AF\u03B1, aitia, \"cause\"; and -\u03BB\u03BF\u03B3\u03AF\u03B1, -logia)."@en .