(a.) Not producing the proper effect; without effect; inefficient; weak; useless; futile; unavailing; as, an ineffectual attempt; an ineffectual expedient.

abortive acarpous aimless arid barren bootless borne celibate childless counterproductive desert desolate drained dried-up dry effete emasculate empty etiolated exhausted failed failing fallow fatuitous fatuous featherweight feckless forceless fruitless futile gaunt gelded ill-qualified impotent inadequate inane incapable incompetent ineffective inefficacious inefficient infecund infertile inoperative invalid invertebrate issueless jejune lame leached lightweight limited maladjusted manque mean meaningless menopausal miscarried miscarrying narrow no go no-account nonfertile nonproducing nonproductive nonprolific not equal to not up to nugacious nugatory of no account of no effect of no force of no use paltry pointless powerless purposeless set sine prole small spineless sterile stickit stillborn successless sucked dry superfluous teemless unable unadapted unadjusted unauthoritative unavailable unavailing uncultivated unequipped unfertile unfit unfitted unfortunate unfruitful unplowed unproductive unprolific unqualified unsown unsuccessful untilled useless vain virgin waste wasted weak without any weight without issue