unviableadjective
/ʌnˈvaɪ.ə.bl̩/not able to work as intended; not able to succeed:
She concluded that the plan was unviable with the resources that were available.
specialized biology not able to continue to exist as, or develop into, a living being:
an unviable pregnancy/foetus
unviability
noun [ U ] uk/ˌʌn.vaɪ.əˈbɪl.ɪ.ti//-ə.t̬i/
the unviability of the plan/pregnancy