Synonyms of the word

unworkable

• adj. Not workable or operable; not practical; unmanageable.
• n. Something that is not workable, or cannot be made to work.

impossible

• adj. Not possible; not able to be done or happen.
• adj. (colloquial, of a person) Very difficult to deal with.
• adj. (mathematics, dated) imaginary.
• n. (obsolete) an impossibility.

impracticable

• adj. Not practicable; impossible or difficult in practice.
• adj. Of a passage or road: impassable.
• adj. (obsolete) Of a person or thing: unmanageable.
• n. (obsolete) An unmanageable person.

infeasible

• adj. Not feasible.

unfeasible

• adj. Infeasible: not feasible.