incapable
adjective
(followed by `of') lacking capacity or ability
“incapable of carrying a tune”
“he is incapable of understanding the matter”
Oppositescapablenot being susceptible to or admitting of something (usually followed by `of')
“incapable of solution”
(followed by `of') not having the temperament or inclination for
“simply incapable of lying”
Oppositescapablenot meeting requirements
“unequal to the demands put upon him”
Source: WordNet 3.1, Princeton University
