What does "Tres Personae" mean in Tertullian's "Una Substantia Tres Personae"? I've read the internet about Tertullian's "tres personae, una substantia" of Trinity. It seems that his "tres personae, una substantia" is rejected by all kind of Christianity.

However I would like to know what the Tertullian's "Tres Personae" mean since from the internet I read about English, the word [Person] has different meaning with [Persona].

Now it seems to me the "Tres Personae" is [Three Persona], not [Three Persons], while in the point of view of the pro-Trinity majority (as far as I know) it's about [Three Persons].

So, my question is – did Tertullian meant of his "Personae" a Person? or a Persona? 

Or did I make mistake which actually in English language, there is no difference between Persona and Person?
The Encyclopedia of Ancient Christianity provides a brief overview of the evolution of the Latin term persona (plural personae), which Tertullian is famous for introducing into discussions on the threeness of God.  It begins with the secular meaning, and then moves to Tertullian's use of the word:


  In addition to the classical meanings of the term persona (role, person and individuality), Latin theology from the very beginning knew of a technical meaning.  [...] Borrowing from secular exegesis that distinguished persona grammatically and aesthetically (dignity or personal character), and under the influence of the legal tradition, [Tertullian] applied a realist meaning to the term (persona = res). (3:153)


Res is the Latin word for "thing" or "entity," which while pointing us in the right direction, perhaps still feels insufficiently specific.  We can turn to J. N. D. Kelly, who writes in Early Christian Doctrines:


  The primary sense of persona was 'mask', from which the transition was easy to the actor who wore it and the character he played.  In legal usage it could stand for the holder of the title to a property, but as employed by Tertullian it connoted the concrete presentation of an individual as such. (115, emphasis added)


So we might say then that the personae of Tertullian are "persons" in the sense of "individuals" or "entities."  But Kelly warns us against anachronistically reading modern understandings of "person" onto Tertullian:


  In neither case, it should be noted, was the idea of self-consciousness nowadays associated with 'person' and 'personal' at all prominent. (115)