Opper rhymes with:
bopper, chopper, clopper, copper, cropper, dropper, gropper, hopper, improper, kopper, popper, proper, propper, shopper, stopper, topor, topper, whopper
Opper sounds like:
o'bara, o'barr, o'berry, o'haver, obar, obara, obarr, ober, oberry, oeuvre, ofer, offer, offerer, ohaver, opera, opere, opfer, oprah, opry, oubre, ovary, over, overhear, overy