crucial

adj

Etymology: 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.

1. Essential or decisive for determining the outcome or future of something; extremely important; vital.

   “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.”

2. Cruciform or cruciate; cross-shaped.
3. Very good; excellent; particularly applied to reggae music.

   “Delbert Wilkins is the most crucial pirate radio DJ in Brixton.”