diagnosis

n. process of identifying a disease from its symptoms, conclusion following a diagnostic exam

In general, diagnosis (plural diagnoses) has two distinct dictionary definitions. The first definition is "the recognition of a disease or condition by its outward signs and symptoms", while the second definition is "the analysis of the underlying physiological/biochemical cause(s) of a disease or condition".
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Diagnosis /di·ag·no·sis/ the determination of the nature of a case of a disease or the distinguishing of one disease from another. [more]Diagnosis - Community and Resources

Noun
1. identifying the nature or cause of some phenomenon
(synonym) diagnosing
(hypernym) designation, identification
(hyponym) blood typing
(derivation) diagnose

n. diagnosis, process of identifying a disease from its symptoms, conclusion following a diagnostic exam