Proprietor's rhymes with:
proprietors, proprietors, proprietors, proprietors, proprietors, rioters, dieters, proprietors, rioters, accelerometers, amphitheaters, arbiters, auditors, capacitors, catheters, competitor's, competitors, conservators, conspirators, contributors, curators, dieters, distributors, distributors', dosimeters, elaters, estimators, executors, exhibitors, inhibitors, inquisitors, interlocutors, interpreters, janitors, jupiter's, kilometers, magnetometers, marketer's, marketers, marketers', micrometers, monitors, odometers, orators, orbiters, parameters, perimeters, picketers, predators, proprietors, rioters, secateurs, senator's, senators, senators', solicitors, theater's, theaters, theatre's, theatres, thermometers, visitor's, visitors, visitors'