when is the vocative case used in latin
Vocative case The vocative case (abbreviated VOC) is the case used for a noun that identifies a person (animal, object etc.) being addressed or occasionally the determiners of that noun. A vocative expression is an expression of direct address by which the identity of the party spoken to is set forth expressly within a sentence. For example, in the sentence "I don't know, John," John is a vocative expression that indicates the party being addressed, as opposed to the sentence "I don't know John" in which "John" is the direct object of the verb "know."
Catholic (term) The word catholic (with lowercase c; derived via Late Latin catholicus, from the Greek adjective καθολικός (katholikos), meaning "universal"[1][2]) comes from the Greek phrase καθόλου (katholou), meaning "on the whole", "according to the whole" or "in general", and is a combination of the Greek words κατά meaning "about" and ὅλος meaning "whole".[3][4] The term Catholic (usually written with uppercase C in English) was first used to describe the Christian Church in the early 2nd century to emphasize its universal scope. In the context of Christian ecclesiology, it has a rich history and several usages.