n. [ L. aetologia, Gr. a'itiologi`a; a'iti`a cause + lo`gos description: cf. F. étiologie. ] 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; etiology. AS [ 1913 Webster ]
2. The assignment of a cause. [ 1913 Webster ]
3. (Med.) The cause or origin of a disease. Now more commonly written etiology. [ PJC + AS ]
n. [ Palæo- + ætiology. ] The science which explains, by the law of causation, the past condition and changes of the earth; the explanation of past events in terms of scientific causes, such as geological causes. -- Pa*læ`ti*o*log"ic*al a. Syn. -- paletiology. [1913 Webster + WordNet 1.5]