Synonyms for Ineffective (same or very similar meaning)
WordNet sense 1 (lacking in power or forcefulness):
ineffectual, unable
WordNet sense 2 (not producing an intended effect):
uneffective
WordNet sense 3 (lacking the ability or skill to perform effectively; inadequate):
inefficient
WordNet sense 4 (not qualified or suited for a purpose):
incompetent
From the ODE community, based on WordNet
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