1. To make a clear but unintentional physical indication of where, when, and how one is going to throw a punch. You've got to stop telegraphing your punches like that, or you're not going to make it very far in the boxing world. The guy went to take a swing at me, but he telegraphed his punch and I was able to duck out of the way.

2. By extension, to do something that unintentionally makes it obvious what one's intentions are or next move will be. I was a little nervous about the interview, but the person conducting it telegraphed their punches, so I was able to answer everything pretty easily. The senator has been telegraphing his punches throughout this entire campaign.