Ornithology, as basically only bird and language fans know, is the scientific study of birds. The word was coined as a New Latin formation by Ulisse Aldrovandi, a pioneer of natural history. He took this from the Greek word ornithologos, which meant the same thing. This was comprised of ornis (meaning "bird" but having a secondary definition of "chicken") and -logia, which, as we've seen many times, meant "the study of" but earlier on meant "word". Ornis has a quick and somewhat contested origin, possibly coming from the Proto-Indo-European reconstruction hern, meaning "eagle" (apparently it became somewhat gentrified in definition over time, but it's still pretty interesting how it meant two different birds before it got broadened). The suffix -logia derives from the verb legein, meaning "to say" and coming from Proto-Indo-European leg, "to gather" (as in gathering words to say). Usage of ornithology peaked in the 1830s, but has relatively flatlined over the last century.
Adam Aleksic, an incoming freshman at Harvard University, has been described as the internet's sixth most famous etymologist. He has disturbing interests in linguistics, vexillology, geography, board games, limericks, and law, and he loves writing about himself in the third person.
The Etymology Nerd