1. Of, relating to, or characteristic of life: See Synonyms at living.
2. Necessary to the continuation of life; life-sustaining: a vital organ; vital nutrients.
3. Full of life; animated: The population of the teeming, vital slum . . . declined(Rick Hampson).
4. Imparting life or animation; invigorating: the suns vital rays.
5. Necessary to continued existence or effectiveness; essential: Irrigation was vital to early civilization(William H. McNeill).A vital component of any democracy is a free labor movement(Bayard Rustin).
6. Concerned with or recording data pertinent to lives: vital records.
7. Biology Used or done on a living cell or tissue: vital dyes; vital staining.
8. Destructive to life; fatal: a vital injury.
[Middle English, from Old French, from Latin vtlis, from vta, life; see gwei- in Indo-European roots.]
vital·ly adv.
vital·ness n.
vital /vatl/ adj.1 most important, absolutely necessary: Water is vital to life.2 energetic, lively: She has a vital personality. n.pl.vitals important organs, such as the heart, lungs, and digestive system: His vitals are in bad condition.-adv.vitally.
va
tl/ adj. 1 most important, absolutely necessary: Water is vital to life. 2 energetic, lively: She has a vital personality. 
n.pl. vitals important organs, such as the heart, lungs, and digestive system: His vitals are in bad condition. -adv. vitally. 
t
l)
lis, from v