2 Syllables: SU
barrel, bethel, carol, carroll, devil, dreadful, eccles, ethel, ethyl, federal, festal, fretful, gentle, gerald, harold, hegel, herald, kennel, kettle, level, levelled, levels, medals, meddle, merrill, metal, methyl, mettle, nestle, nettle, pebble, pedal, peril, pestle, petal, phenol, rebel, revel, revelled, revels, reynolds, settle, special, speckled, spectral, sterile, treble, vessel, vestal, wrestle
3 Syllables: USU
ancestral, dishevelled, especial, ezekiel, fitzgerald, forgetful, imperil, imperilled, neglectful, orchestral, projectile, respectful, unsettled
4 Syllables: UUSU
accidental, continental, departmental, detrimental, disrespectful, elemental, fundamental, instrumental, monumental, oriental, sentimental, transcendental
5 Syllables: UUUSU
6 Syllables: UUUUSU
Found 78 words across 5 groupings. Skipped 22 excess words of a similar stem.