Onomastics or onomatology is the study of proper names of all kinds and the origins of names. The words are from the Greek: "ὀνομαστικός" (onomastikos), "of or belonging to naming" and "ὀνοματολογία" (onomatologia), from "ὄνομα" (ónoma) "name". Toponymy or toponomastics, the study of place names, is one of the principal branches of onomastics. Anthroponomastics is the study of personal names.