crucial

adjective
UK /ˈkruː.ʃəl/
US /ˈkruː.ʃəl/

Very, very important and needed.

Getting enough sleep is crucial for doing well at school.


OTHER MEANINGS

2. Extremely important because it decides how something will turn out.

The final goal was crucial to winning the game.

3. Needed to make something work or succeed.

Water is crucial for plants to grow.

4. A moment or choice that changes everything that comes after.

It was a crucial moment in the story when she found the map.