The phrase "an unviable" is correct and usable in written English.
It can be used when describing something that is not capable of working successfully or is not feasible.
Example: "The proposed plan was deemed an unviable solution to the problem."
Alternatives: "an impractical" or "a nonviable".
An unbalanced endosperm may lead to an unviable seed (Costa et al. 2004).
"They are interrupting an unviable pregnancy".
It's an unviable, untenable position".
This cost can make the difference between an economically viable and an unviable CCS project.
Repsol's alleged failure threatened to "practically turn us into an unviable country," Kirchner said.
"Subsidising infrastructure for an unviable and foreign-owned mining project will inevitably mean more worthy local investments will miss out".
The 8th Amendment was designed to legislate against abortion, yet experts note the woman in the current case, who is being kept alive effectively as an incubator for an otherwise unviable fetus, did not request an abortion.
Line-catching is more ethical but it's becoming an increasingly unviable way to make a living, says Peter Williams, who fishes out of Emsworth and will be supplying the Chichester Catchbox scheme.
Supporters of CAP say that the economic support which it gives to farmers provides them with a reasonable standard of living, in what would otherwise be an economically unviable way of life.
It seems difficult to believe now that being in a guitar band is considered a financially unviable hobby like model trains or World War II reenactments, but back then indie had captured the city's imagination.
This raises the question of whether it is plausible to have such a large number of disruptive gene changes without rendering a genome unviable.
