See vital in Webster's New World Roget's A-Z Thesaurus II
adjective
Marked by or exhibiting life:
alive, animate, animated, live2, living. See liveFull of vigor:
able-bodied, iron, lusty, red-blooded, robust, strapping, sturdy, vigorous. See strongConstituting or forming part of the essence of something:
basic, constitutional, constitutive, essential, fundamental, integral. See be, surfaceCausing or tending to cause death:
deadly, deathly, fatal, lethal, mortal. See live
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