Carnivals rhymes with:
carnival's, carnival's, carnival's, carnival's, carnival's, festivals, approvals, archrivals, arrivals, carnival's, crovls, daredevils, devil's, devils, devils', evils, festival's, festivals, hovels, intervals, level's, levels, marvel's, marvels, nevels, nevils, novel's, novels, removals, revels, revivals, rival's, rivals, rivals', shovels, sivils, swivels, travels, unravels, upheavals, weevils
Carnivals sounds like:
carnival's, chernobyl's, crumbles