Well, it is really hard to give a textbook definition of gongfu in terms of "you use a 100 ml yixing pot, 6 grams of oolong, water at 190ºf, etc" because it is sort of an art form and there are so many different ways to go about it. You can use a gaiwan, you can use a small yixing pot...you can use sipping cups, you can use cup sets with an aroma cup and a sipping cup... There are bajillions of variations in terms of the basic stuff you use and how you steep.
But gongfu does have the basic things I listed before in common.
Semi-gongfu (or 'wrongfu' if you're feeling funny) is even more ambiguous. You might, for instance, use a gaiwan or yixing, but use brewing parameters more like the English method (little leaves, lots of time). You might even use the gongfu parameters, but pay little attention to any thing resembling a ceremony. (Gongfu, whatever the varient, always seems to have an emphasis on form and aesthetic appeal...forgot to mention that.)
That's sort of lame...but it's the best I can do for short 'definitions' at the moment.