2 Syllables: SU
adjunct, Arian, Aryan, ashen, Ashton, aspen, Aston, Athens, audience, Austin, Austrian, awesome, bastion, blossom, Boston, Caspian, caution, chasm, craftsman, Dawson, draughtsman, fashion, fasten, fathom, Gaston, Grafton, Hadrian, Hodgson, Hoffman, Hoffmann, jasmine, javelin, Latham, Lawson, lodgment, Marian, Masson, Moslem, Nostrand, nostrum, often, pageant, passion, province, ration, rostrum, saffron, savants, soften, sovereign, spasm, watchman
3 Syllables: USU
assassin, attachment, compassion, detachment, exhaustion, harassment, imagine, impassioned, oldfashioned, potassium, precaution, Sebastian
4 Syllables: USUU
Found 65 words across 3 groupings. Skipped 27 excess words of a similar stem.