Lacking the necessary ability, capacity, or power.adjective
Unable to perform adequately; incompetent.adjective
Not susceptible to action or treatment.adjective
Not meeting the physical and mental requirements imposed by law for the performance of a particular task.adjective
Not meeting the requirements necessary for proper legal functioning.
Lacking sufficient capacity or capaciousness; insufficient, unfit, or unqualified: in this and the succeeding uses commonly followed by of.
Not capable of receiving or admitting; not susceptible: as, his lot is incapable of amelioration.