This is the verse translation, not a definition of the individual word.
O People of the Book, there has come to you Our Messenger[1], making things clear to you, after an interval between the messengers, so you do not say, “No bearer of glad tidings or a warner has ever come to us.” Now there has come to you a bearer of glad tidings and a warner. And Allah is Most Capable of all things.
Source
[1] The only Prophet sent after Jesus (عليه السلام) was Muhammad (ﷺ).