Or search: diencephalon, thalmencephalon
2 Syllables: SU
cabinets
3 Syllables: SUU
amorous, animates, aqueducts, avarice, callousness, Calvinist, clamorous, fatuous, glamorous, graduates, Lazarus, naturalist, ravenous, satirist, valorous
4 Syllables: USUU
analogous, antagonist, calamitous, gelatinous, magnanimous, paralysis, protagonist, unanimous
5 Syllables: UUSUU
pusillanimous, undergraduates
6 Syllables: UUUSUU
psychoanalysis

Found 27 words across 5 groupings. Skipped 3 excess words of a similar stem.