Or search: organism, anabolism, catabolism, glycolysis, katabolism, respiration, hemimetaboly, holometaboly, metamorphosis, dissimilation, heterometaboly, hemimetamorphosis
3 Syllables: SUU
dualism, nihilism
4 Syllables: SUUU
aphorism, cataclysm, catechism, fatalism, federalism, feudalism, formalism, journalism, mannerisms, naturalism, pluralism, socialism, symbolism, vandalism
5 Syllables: USUUU
anachronism, antagonism, colonialism, fanaticism, imperialism, industrialism, materialism, paternalism, provincialism
6 Syllables: UUSUUU
sentimentalism
6 Syllables: UUUSUU
individualism

Found 27 words across 5 groupings. Skipped 2 excess words of a similar stem.