Source : Webster's Revised Unabridged Dictionary (1913)

Nosology \No*sol"o*gy\, n. [Gr. ? disease + -logy: cf. F.
   nosologie.]
   1. A systematic arrangement, or classification, of diseases.

   2. That branch of medical science which treats of diseases,
      or of the classification of diseases.

Source : WordNet®

nosology
     n : the branch of medical science dealing with the
         classification of disease [syn: {diagnostics}]