The word agony was first used in English in a late fourteenth-century translation of the Bible by theologian John Wycliffe, with the spelling agonye. It seems that Wycliffe borrowed the word directly from Latin agonia, which had the same definition. That comes from an Ancient Greek noun also sounding like agonia but meaning "struggle" or "competition" (the connection was that agony was considered a kind of mental struggle). The root in agonia is agon, meaning "competition" (also the etymon of protagonist and antagonist) and ultimately deriving from the Proto-Indo-European root ag, "to draw out" or "move". Usage of the word agony in literature over time has been steadily declining since a peak in the late 1860s.
Hello! I'm Adam Aleksic. This year, I graduated from Harvard University with a degree in Government and Linguistics. There, I co-founded the Harvard Undergraduate Linguistics Society and wrote a thesis on Serbo-Croatian language policy, magna cum laude. In addition to etymology, I also really enjoy philosophy, trivia, vexillology, geography, board games, conlanging, art history, and law.