Dropper rhymes with:
cropper, gropper, improper, proper, propper, bopper, chopper, clopper, copper, cropper, gropper, hopper, improper, kopper, opper, popper, proper, propper, shopper, stopper, topor, topper, whopper
Dropper sounds like:
derryberry, draper, drapery, driever, driver, drover