Or search: decency, decorum, modesty, behavior, demeanor, improper, primness, behaviour, rightness, demeanour, deportment, correctness, appropriateness
2 Syllables: SU
diaries
3 Syllables: SUU
diocese, dynasties, inquiries, piety, primaries, privately, quietly
3 Syllables: USU
enquiries
4 Syllables: USUU
advisedly, anxieties, anxiety, decidedly, excitedly, propriety, psychiatry, refineries, reliably, sobriety, varieties, variety
5 Syllables: UUSUU
impropriety, indescribably, notoriety, undeniably

Found 25 words across 5 groupings. Skipped 1 excess word of a similar stem.