Grave, vital (5)
I believe the answer is:
acute
(Other definitions for acute that I've seen before include "Shrewd; severe" , "Excruciating" , "Perspicacious" , "Severe, penetrating" , "Short and severe" .)
I believe the answer is:
acute
(Other definitions for acute that I've seen before include "Shrewd; severe" , "Excruciating" , "Perspicacious" , "Severe, penetrating" , "Short and severe" .)