See inefficient in Webster's New World Roget's A-Z Thesaurus II
adjective
Lacking the qualities, as efficiency or skill, required to produce desired results:
inapt, incapable, incompetent, inept, inexpert, unskilled, unskillful, unworkmanlike. See abilityNot having the desired effect:
ineffective, ineffectual, inefficacious, useless. See affect
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