Synonyms of ineffectual

1 Syllable
vain, paled, wan, weak
2 Syllables
paler, drossy, pointless, mousier, wannest, palest, feeblest, idle, scrapper, paltry, wanner, feebler, worthless, fruitless, pithless, no-good, paltrier, doughier, doughy, strengthless, bootless, feckless, mousy
3 Syllables
no-account, impotent, resultless, faint-hearted, useless, spineless, futile, unable, slack-spined, impuissant, unfitted, hopeless, powerless
4 Syllables
abortive, inutile, unusable, nongermane, unavailing, improficient, insufficient, wishy-washy, unsuccessful, nonfunctional, unratified, incompetent, unusuable, inefficient, unfunctional
5 Syllables
unworkmanlike, inadequate, unconsequential, amoebalike, unproductive, unenforceable, ineffective, disenfranchised