Where did that name come from

Just getting started processing images from Vietnam. One of the challenges in visiting Vietnam is that it is not only a new country for us, but a new continent. We had never been to Asia before. Not only were there different birds, even the names of the birds were much different than we were accustomed to. Yes, there are 360 species of hummingbirds in the Americas, but all these hummingbirds have many similarities. In Vietnam, we were seeing Drongos, Shamas, Bulbuls, and Babblers. This is one of those birds-a Greater Racket-tailed Drongo. Certainly we can see where the “racket” comes from, and I assume there is a “lesser” out there somewhere too. But where did the “Drongo” come from?