Preacher or Theologian?

[JoeyKnothead]

What's the difference twixt a preacher and a theologian?

I googled it and the closest I got was:

1. A preacher is a proclaimer of the word of God.
2. A Priest represents the people before God.
3. A Pastor is the shepherd of a flock, that is the leader of a church. He guides his flock in a life in Christ.
4. There is only one Father, and that is our Father in heaven. I know that Catholic priests are referred to as Father.

So what's a theologian? I'm thinking they just study and don't go about preaching, but I'm a simpleton, I know I'm missing something here. If a theologian holds a lecture, has he just become a preacher?

[McCulloch]

A theologian is a scholar who studies theology. In an informal sense then, every preacher, evangelist, pastor and priest must be so some degree a theologian. But the term is usually reserved for those who have formally studied and written about theology in an academic capacity. For modern theologians, look for a degree (Master of Theological Studies, Master of Divinity, Master of Theology, Master of Sacred Theology, Doctor of Theology, Doctor of Divinity, Doctor of Sacred Theology or Doctor of Philosophy).

A theologian can preach or not. Many Roman Catholic theologians are priests. The categories are not mutually exclusive.

Notice how I have answered the question about what distinguishes a theologian from preacher, evangelist, minister, pastor and priest without actually addressing what is theology.