Kopper rhymes with:
copper, bopper, chopper, clopper, copper, cropper, dropper, gropper, hopper, improper, opper, popper, proper, propper, shopper, stopper, topor, topper, whopper
Kopper sounds like:
kafer, kapfer, kapoor, kapor, kapper, kapur, kaspar, kasper, kaufer, kaypro, keefer, keeper, keever, kefauver, keffer, keifer, keiffer, keiper, kever, kiefer, kieffer, kieper, kifer, kiper, kipfer, kipper, kippur, kober, kochevar, koper, kopera, kovar, kover, kuiper, kuper, kupfer, kupor, kupper, kuyper