-stiks noun plural but usually singular in construction
Etymology: modification (influenced by English -ics ) of French onomastique, from onomastique onomastic, from Greek onomastikos
1.
a. : the science or study of the origins and forms of words especially as used in a specialized field (as science or commerce)
a course in onomastics
b. : the science or study of the origin and forms of proper names of persons or places
any student of onomastics and of surnames in particular — Otto Springer
2. : the system underlying the formation and use of words especially for proper names or of words used in a specialized field
according to rules of Indo-European onomastics — E.E.Herzfeld