1. Capable of success or continuing effectiveness; practicable: a viable plan; a viable national economy. See Synonyms at possible.
a. Capable of living, developing, or germinating under favorable conditions: viable spores.
b. Capable of living outside the uterus. Used of a fetus or newborn.
[French, from vie, life, from Old French, from Latin vīta; see gwei- in the Appendix of Indo-European roots.]
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