life-sustaining

from WordNet (r) 3.0 (2006)

life-sustaining
    adj 1: 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" [syn: {vital}, {life-sustaining}]

from The Collaborative International Dictionary of English v.0.48

life-sustaining \life-sustaining\ adj.
   being the seat or source of life; performing a necessary
   function in the living body; as, the need for life-sustaining
   air and water.

   Syn: vital.
        [WordNet 1.5 +PJC]

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