Here's what rhymes with oligopolio.
polio oleo no so know go though although low show co row tho fo foe ho lo bo doe dough mo po ro toe wo woe folio tow yo beau ceux faut goe hoe jo ko sew soe vo beaux cho dau mow noe roe sho yeux zo rho whoa doh resew ago flow ratio blow grow radio slow snow throw pro glow quo audio fro crow patio stereo thro bio forego forgo uno floe rodeo topos tuo bro stow throe trow adagio sloe regrow kayo pekoe borzoi romeo tallyho schmo schmoe below embryo plateau studio bestow chateau hello nouveau propos tableau aglow aliquot cameo dicho spatio tableaux chateaux dunno plateaux trousseau braggadocio chapeau kapok tarot turbot deathblow foreknow bandeau gateau chapeaux gateaux trousseaux overthrow portfolio undergo buffalo overflow portico calico dynamo apropos domino escrow outgrow siglo oregano piccolo pistachio undertow overgrow matzoh fatso mustachio moustachio indigo archipelago bungalow politico vertigo medico mistletoe presidio afterglow pompano microdot impresario pianissimo generalissimo