Here's what rhymes with unusefully.
usefully Words that almost rhyme with unusefully
youthfully truthfully untruthfully ruefully fruitfully uselessly euphony tunefully unity brutally mutiny eulogy gloomily lunacy moodily neutrally frugally futilely gruesomely broodily community beautifully immunity jewelry acuity annuity suitably humanly ruthlessly futurity fruitlessly unsuitably contumelies woozily snootily scrutiny fluency crucially fluently prudently stupidly truancy congruity contumacy garrulity irreducibly humourlessly presumably credulity disunity vacuity autoimmunity imprudently impudently immovably tenuity translucency glamourously opportunity ambiguity ingenuity contiguity continuity importunity perspicuity excusably exiguity promiscuity inexcusably