See incapable in Webster's New World Roget's A-Z Thesaurus II
adjective
Lacking capability:
inadequate, incompetent, unequal, unfit, unqualified. See ability, excessLacking the qualities, as efficiency or skill, required to produce desired results:
inapt, incompetent, inefficient, inept, inexpert, unskilled, unskillful, unworkmanlike. See abilityNot capable of accomplishing anything:
helpless, impotent, inadequate, ineffectual, powerless, weak. See ability, strong
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