The word confess was borrowed from Old French in the late 1300s as the Middle English word confessen. Across the English Channel, it took the form of confesser, with the same definition. That comes from the Latin word confessare, which is composed of the prefix con-, meaning "with", and fessare, or "to admit". So a confession is a discussion "with admission" of guilt. Con-, through Proto-Italic kom, derives from Proto-Indo-European kom, which could mean many things, including "next to", "at", and "with". Fessare, meanwhile, also came from Proto-Italic and PIE, going back to the reconstruction beh, meaning "speak". Usage of the word confess in literature over time peaked in the late seventeenth century and has been decreasing since then, perhaps parallelism society's increasing secularism.
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.