Onion rhymes with:
bunyan, grunion, munyan, munyon, runnion, runyan, runyon, banyan, bennion, binion, branyon, bunyan, californian, canion, canyon, catalonian, communion, companion, disunion, dominion, gagnon, grunion, henion, kenyan, kenyen, kenyon, kinion, kinyon, lanyon, macedonian, mannion, minion, munyan, munyon, nonunion, o'banion, obanion, opinion, pinion, pinyan, reunion, runion, runnion, runyan, runyon, soviet-union, union, virginian
Onion sounds like:
o'hanian, o'mahoney, o'mahony, oana, oanh, oehme, oehmen, oeien, ohanian, ohioan, ohm, ohmae, ohman, ohmann, oien, oma, omaha, omahoney, omahony, oman, omani, omen, ommen, omni, omonia, on, ona, onan, onawa, one, one-way, oney, onnen, onni, onno, ono, oona, owen, own, oyama, oyen