Halcyon is a rather nice adjective used to refer to the idyllic golden days of yore, but many people do not know that the word also denotes a genus of kingfishers. Both of these definitions are connected: they trace to Latin alcyon, which described the bird. In Roman mythology, the alcyonei dies (or "halcyon days") comprised a two-week period around the winter solstice when a fictional kingfisher-like bird was supposed to hatch its offspring, causing the seas to be calm and navigable (hence the connection). Alcyon comes from the Ancient Greek word alkyon, which has an unknown origin but is thought to ultimately be from a non-Indo-European pre-Greek language. Since it was borrowed into English in the 1540s, the word halcyon has had relatively constant use in literature over time, peaking in 1810.
Hello! I'm Adam Aleksic, a sophomore studying government and linguistics at Harvard University, where I co-founded the Harvard Undergraduate Linguistics Society. In addition to etymology, I also really enjoy politics, vexillology, geography, board games, conlanging, and law.