From LookUp: Onomastics (or, in older texts, onomatology) is the study of the etymology, history, and use of proper names. An orthonym is the proper name of the object in question, the object of onomastic study.
Onomastics can be helpful in data mining, with applications such as named-entity recognition, or recognition of the origin of names. It is a popular approach in historical research, where it can be used to identify ethnic minorities within wider populations and for the purpose of prosopography.