Finian's rhymes with:
argentinians, augustinians, carolinians, palestinian's, palestinians, palestinians', albanians, amazonians, argentinians, armenians, athenians, augustinians, babylonians, bosnian's, bosnians, bostonians, caledonian's, carolinians, chechnyan's, chechnyans, estonians, indianians, iranians, iranians', jacksonians, jeffersonians, jordanians, lithuanians, louisianians, oregonians, orleanians, palestinian's, palestinians, palestinians', panamanians, pennsylvanians, romanians, smithsonian's, stepanian's, ukrainian's, ukrainians, washingtonians
Finian's sounds like:
famines, famous, fan's, fancies, fancy, fanech, fanech's, fang, fangs, fanguy, fanning, fanning's, fans, fans', fanuc, fanucchi, faunce, fawning, fayanjuu, fein's, femsa, fence, fences, fenech, feng, fennessey, fennessy, fenske, fenwick, fiance, fiancee, fibonacci, fiennes, finance, finances, financo, finanz, finanza, finazzo, finch, finches, finck, fincke, fines, finesse, finex, finicky, fining, finish, finishes, fink, fink's, finke, finks, finn's, finnick, finning, finnish, finns, finocchio, fins, finunc, foaming, foams, fomon's, fones, fong, fons, fonseca, fonz, fonzie, foong, fumes, fuming, funches, funchess, funck, funes, fung, fung's, fungi, fungus, funk, funke, funks, funky, funniness, funs