The Collaborative International Dictionary
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
adj. 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]
Usage examples of "life-sustaining".
So Phoenix carried the bootstrap components for that construction, the algaes and the cultures for a station's life-sustaining tanks, the plans and the circuit maps, the diagrams and the processes and the programs, the data and the detail.
The pigs were keeping their squat bodies sealed up as much as possible, maintaining an inner reservoir of life-sustaining Air.
Instead of these /oy-giving, life-sustaining plants there was a hidden tree, useless except that its wood when dried yielded a persistent perfume, and this was the tree of death, the sandalwood tree.
He had even met Baron Jalator once, a small man who had refused Arkus' offer of the life-sustaining drug to stave off the encroachment of age.