vital

adjective

1. 1

   manifesting or characteristic of life

   a vital, living organism

   vital signs

2. 2

   full of spirit

   a dynamic full of life woman

   a vital and charismatic leader

3. 3

   performing an essential function in the living body

   vital organs

   blood and other vital fluids

4. 4

   urgently needed; absolutely necessary

   a critical element of the plan

   critical medical supplies