Or search: unjust, unlawful, illegitimate
2 Syllables: SU
bronchial, Connell, consul, Cromwell, Donald, Mongol, Ronald, tonsils
3 Syllables: USU
ensemble, Macdonald, McDonald
4 Syllables: UUSU
horizontal, unexampled

Found 13 words across 3 groupings. Skipped 1 excess word of a similar stem.