Or search: muscle, mastery, tyranny, dominion, genetics, lordship, monopoly, imperium, ascendant, despotism, supremacy, ascendent, ascendance, ascendancy, ascendency
3 Syllables: SUU
complement, consonance, consonant, continence, continent, dominant, Donovan, fraudulent, Jonathan, monument, Ottoman, prominence, prominent, Protestant, Providence, Solomon, Solomon's, tolerance, tolerant
4 Syllables: USUU
concomitants, diocesan, improvidence, incontinence, intolerance, intolerant, predominance, predominant, reconnaissance
4 Syllables: UUSU
concomitant
5 Syllables: UUSUU
cosmopolitan, metropolitan, Neapolitan

Found 32 words across 4 groupings. Skipped 5 excess words of a similar stem.