Nosology (from Ancient Greek νόσος (nosos) 'disease', and -λογία (-logia) 'study of') is the branch of medical science that deals with the classification of diseases. Fully classifying a medical condition requires knowing its cause (and that there is only one cause), the effects it has on the body, the symptoms that are produced, and other factors. For example, influenza is classified as an infectious disease because it is caused by a virus, and it is classified as a respiratory infection because the virus infects and damages certain tissues in the respiratory tract. The more that is known about the disease, the more ways the disease can be classified nosologically.
https://en.wikipedia.org/wiki/Nosology

See also: https://www.google.ru/search?q="nosological form"&newwindow=...

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Note added at 18 мин (2023-06-27 11:06:59 GMT)
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нозологическая форма
nosological form
[греч. nosos — болезнь и logos — учение, наука; лат. form — форма]
определенная болезнь, выделенная на основе установленных этиологии и патогенеза и/или характерной клиникоморфологической картины; единица номенклатуры и классификации болезней.
Syn: нозологическая единица

Толковый биотехнологический словарь.
https://translate.academic.ru/нозологическая форма/ru/en/