Your broker tells you he has a great investment that is not for everyone. This is a private deal that only you (and perhaps a few special others) can get in on. Then he tells you to make out a check to him or some entity other than his firm. The broker is selling away. It can (and will if he is caught) get him fired and will often cause you a very large loss.
If your broker makes this pitch to you, get help and get a new broker. If you are a victim of Selling Away you may have a claim against his firm.