Or search: unequal, inadequate, unacceptable, disappointing, dissatisfactory
2 Syllables: SU
actually
3 Syllables: SUU
Aberdeen, batteries, battery, factories, factory, flatteries, flattery, latterly, laxity, rhapsody, Saturday, Saxony, tactfully, Thackeray
4 Syllables: USUU
olfactory, refractory
4 Syllables: UUSU
satisfactory
5 Syllables: UUSUU
manufactories, manufactory, satisfactorily

Found 21 words across 5 groupings. Skipped 1 excess word of a similar stem.