capable of living.

Physiology .

physically fitted to live.

(of a fetus) having reached such a stage of development as to be capable of living, under normal conditions, outside the uterus.

Botany . able to live and grow.

vivid; real; stimulating, as to the intellect, imagination, or senses

a period of history that few teachers can make viable for students.

practicable; workable

a viable alternative.

having the ability to grow, expand, develop, etc.

a new and viable country.

adjective

impossible , unachievable , unpractical , unreasonable

adjective

applicable , doable , feasible , operable , possible , usable , within possibility , workable , practicable , living , reasonable