crucial

Origin: 1706, from , a medical term for ligaments of the knee (which cross each other), from Latin cross (English crux), from the . The meaning “decisive, critical” is extended from a logical term, Instantias Crucis, adopted by Francis Bacon in his influential Novum Organum (1620); the notion is of cross fingerboard signposts at forking roads, thus a requirement to choose. Origin information sourced from Wiktionary contributors (CC BY-SA 4.0).