St. augustine reveals it in his book city of god. That is where I first learned of the meaning. St. Augustine talks about how the names of the gods coincide with their function. And, in this case, the roman god's name was vaticanus or vagitanus. And, vaticanus was the roman god "who presides over the beginning of first speech aka crying and wailing. Vaticanus was the wail of the baby. With that said, now you possibly know the meaning of vatican. And, it makes me wonder, that it's no wonder women want to be priests.