What rhymes with the word Popper?

Translate Popper to

British philosopher (born in Austria) who argued that scientific theories can never be proved to be true, but are tested by attempts to falsify them (1902-1994) more »

2 syllables

bopper chopper clopper copper cropper dropper gropper hopper kopper opper popper proper propper shopper stopper topor topper whopper

3 syllables

improper