Or search: mortal, worker, gardner, someone, gleaner, somebody, taxation, collector, conductor, accumulator
2 Syllables: SU
bachelor, bachelor's, traveler
3 Syllables: SUU
afterward, amateur, caliber, flatterer, gatherer, janitor, Latimer, manager, massacre, Staffordshire, traveller, vascular
4 Syllables: USUU
ambassador, coadjutor, diameter, examiner, parameter
6 Syllables: UUUSUU
cardiovascular

Found 21 words across 4 groupings. Skipped 12 excess words of a similar stem.