4 Syllables: SUUU
Calvinism, communism, despotism, federalism, heathenism, humanism, mechanism, Methodism, organism, paganism, pessimism, television, terrorism, unionism
5 Syllables: USUUU
7 Syllables: UUUSUUU
Found 19 words across 3 groupings. Skipped 1 excess word of a similar stem.