3 Syllables: SUU
densities, density, enmities, enmity, entity, Kennedy, remedies, remedy, sensibly, splendidly
4 Syllables: USUU
amenities, contentedly, extremities, extremity, identity, indemnity, insensibly, lamentably, nonentity, ostensibly, propensities, serenity, solemnities, solemnity
5 Syllables: UUSUU
indispensably

Found 25 words across 3 groupings.