what is reformed?

What does it mean to be reformed? The reason I ask is because we were going over some philosophy of ministry stuff at our leadership meeting in church, and it came up that we have to ascribe to the "basic tenets of the reformed faith". My first thought was that most of the people on the team probably didn't know much about the reformed faith. So I pose the question to my many readers.. but this is what I'm thinking about:

If you're debating with another evangelical, usually if you say you're reformed, you mean that you believe in predestination and TULIP, or at least TUIP.. But, historically, reformed means Protestant, as distinct from Roman Catholic; in other words, reformed means you hold to the 5 solas: sola scriptura, sola fide, sola grati, soli deo gloria, and sola ? (I always forget that one!).

Of course, in the early Reformation, there wasn't such theological splintering. But I thought it was worth asking. So which is it?