Septimus rhymes with:
altemus, altemus, doremus, ohnemus, altemus, amis, aramis, ausmus, bartmess, bemiss, caccamise, camus, deramus, doremus, emmis, ermis, imprimis, kalmus, loomis, mamis, namis, ohnemus, polhamus, premise, rasmus, sammis
Septimus sounds like:
shafting, shifting, sifting, softening, softens, softimage, softness, speeding, spitting, spotting, spouting, sputnik, sputniks, subatomic, subduing, subotnick, swiftness