What is synthetic theology? In a comment conversation on another question I suspect (at the chastisement of my interlocutor) I may have misused the term "synthetic theology" (or, perhaps, theological synthesis?). 

I think I had in mind that the term intends bringing together multiple passages to form a cohesive theology. Am I off-base here? What is meant by this term?
Yes, this is the same as "systematic theology". Systematics looks at the Bible in a logical fashion, whereas biblical theology looks at the Bible in its revealed order and tries to make sense of the overarching flow and history of redemption. Many commentators believe that systematics has nothing to do with exegesis or biblical theology, but nothing could be further from the truth. 

If you start from the doctrine that the Scriptures are infallible, inerrant, and inspired (which I do), and that they are the only ultimate rule for faith and practice, then I think the best way to think of both systematics and biblical theology is an ever-evolving, constantly re-calibrating synthesis of all understood passages in Scripture. Scripture interprets Scripture (analogy of faith). Whenever a particular interpretation of a passage comes to be known as incorrect, you have to root out all misunderstandings based on that misinterpretation, and then incorporate the better interpretation into your systematics and biblical theology. Systematics and biblical theology both work this way. The difference is in the emphases and the order in which they go about looking at Scripture. a_hardin has posted a useful answer here that gets at what I'm saying.