not capable of being carried out or put into practice; "refloating the sunken ship proved impracticable because of its fragility"; "a suggested reform that was unfeasible in the prevailing circumstances"
If you say that something is unfeasible, you mean that you do not think it can be done, made, or achieved. The weather made it unfeasible to be outdoors The board said the idea was unfeasible. = impractical feasible