Japan's rhymes with:
japans, japans, japans, pan's, pans, span's, spans, ann's, anne's, ban's, bans, branz, caen's, can's, cannes, cans, cezanne's, chan's, cheyenne's, cheyennes, clans, crans, dan's, danz, diane's, fan's, fans, fans', frans, franz, franze, gans, ganz, glanz, hannes, iran's, jan's, jans, janz, japans, kanz, klan's, klans, krans, kranz, lanz, man's, mann's, mannes, manns, mans, manz, mccann's, minivans, nan's, pan's, pans, pecans, plan's, plans, plans', rans, ranz, roseanne's, sannes, sans, sanz, scans, sedans, span's, spans, stan's, sudan's, tans, trans, vans
Japan's sounds like:
jabbing, japanese, japans, japonica, javanese, jawboning, jifeng, jiving, josephine's