(ת') עקר, חסר תועלת; כושל, שעלה בתוהו; חסר ערך

adj. fruitless, unproductive; unsuccessful; worthless; frivolous

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Adjective
1. producing no result or effect; "a futile effort"; "the therapy was ineffectual"; "an otiose undertaking"; "an unavailing attempt"
(synonym) ineffectual, otiose, unavailing
(similar) useless
2. unproductive of success; "a fruitless search"; "futile years after her artistic peak"; "a sleeveless errand"; "a vain attempt"
(synonym) bootless, fruitless, sleeveless, vain
(similar) unproductive

adj. futile, vain, pointless; trifling, idle, trivial; frivolous, piffling, shallow, stingy, fiddling

adj. futile, trifling, trivial, peddling, shallow