The adj vital has 4 senses (first 1 from tagged texts)
1. (6) critical, vital -- (urgently needed; absolutely necessary; "a critical element of the plan"; "critical medical supplies"; "vital for a healthy society"; "of vital interest")
2. vital, life-sustaining -- (performing an essential function in the living body; "vital organs"; "blood and other vital fluids"; "the loss of vital heat in shock"; "a vital spot"; "life-giving love and praise")
3. full of life, lively, vital -- (full of spirit; "a dynamic full of life woman"; "a vital and charismatic leader"; "this whole lively world")
4. vital -- (manifesting or characteristic of life; "a vital, living organism"; "vital signs")