2 Syllables: SU
adjunct, ashen, Ashton, asking, aspen, aspirin, Aston, Athens, baffling, basking, bastion, blasting, Caspian, casting, catching, Catharine, Catherine, chasm, clashing, clasping, craftsman, crashing, dashing, dazzling, drafting, draughtsman, fashion, fasten, fastening, fastens, fasting, fathom, flashing, gasping, Gaston, grafting, Grafton, grasping, hatching, having, javelin, Katharine, Katherine, lashing, lasting, Latham, laughing, masking, massing, Masson, matching, pageant, passing, passion, patching, rasping, ration, rationing, rations, saffron, savants, scratching, slashing, smashing, snatching, spasm, splashing, staffing, thrashing, traveling, travelling
3 Syllables: USU
amassing, assassin, attaching, attachment, compassion, contrasting, despatching, detaching, detachment, dispatching, harassing, harassment, imagine, impassioned, oldfashioned, potassium, Sebastian, surpassing, unravelling
4 Syllables: UUSU
Found 91 words across 3 groupings. Skipped 17 excess words of a similar stem.