2 Syllables: SU
3 Syllables: SUU
bearable, cerebral, clerical, decimal, edible, equable, festival, flexible, genital, legible, medical, parable, pedestal, plentiful, preferable, Reginald, seminal, several, skeletal, skeptical, spectacle, tenable, terrible
4 Syllables: USUU
acceptable, accessible, amenable, chimerical, confessional, congenital, Congressional, delectable, detectable, detestable, ephemeral, execrable, illegible, impeccable, impregnable, incredible, ineffable, inflexible, numerical, perceptible, polemical, professional, receptacle, regrettable, respectable, susceptible, unbearable, untenable
5 Syllables: UUSUU
hypothetical, inaccessible, incontestable, indigestible, inexpressible, irrepressible, unacceptable, unforgettable
6 Syllables: UUUSUU
Found 62 words across 5 groupings. Skipped 7 excess words of a similar stem.