1706, from French crucial, a medical term for ligaments of the knee (which cross each other), from Latin crux, crucis (“cross”) (English crux), from the Proto-Indo-European *(s)ker- (“to turn, to bend”).
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. Specific quote is:
- Inter praerogativas instantiarum, ponemus loco decimo quarto Instantias Crucis; translato vocabulo a Crucibus, quae erectae in biviis indicant et signant viarum separationes.
- Being essential or decisive for determining the outcome or future of something; extremely important.
- The battle of Tali-Ihantala in 1944 is one of the crucial moments in the history of Finland.
- A secure supply of crude oil is crucial for any modern nation, let alone a superpower.
- (archaic) Cruciform or cruciate; cross-shaped.
- (slang, chiefly Jamaica) Term of approval, particularly when applied to reggae music.
- Delbert Wilkins is the most crucial pirate radio DJ in Brixton.
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From a root of Latin crux.
From English crucial.
crucial m and f (plural cruciales)