2 Syllables: SU
Brussels, bustle, circle, Colonel, cudgel, fertile, girdle, Herschel, hovel, hurdle, hurtful, hustle, Journal, kernel, Lovell, muffled, muscle, muzzle, myrtle, purple, puzzle, ruffle, Russel, Russell, Russell's, rustle, scuffle, servile, shovel, shuffle, thermal, turtle, verbal, vernal, Virgil
3 Syllables: USU
commercial, dispersal, distrustful, diurnal, encircle, eternal, external, fraternal, industrial, infernal, internal, maternal, nocturnal, paternal, proverbial, rehearsal, reversal, unruffled
4 Syllables: UUSU
5 Syllables: UUUSU
Found 56 words across 4 groupings. Skipped 25 excess words of a similar stem.