2 Syllables: SU
7, Aaron, barium, Baron, barren, beckon, Bedlam, bellum, Bremen, brethren, Breton, burthen, carrion, cession, chairman, Clarence, clarion, Clemens, Clement, crescent, currant, deaden, deference, Devon, Edwin, Ellen, errand, errant, Essen, essence, Evan, felon, freshened, harem, heaven, Helen, herdsman, heron, Hessian, leaden, leaven, Leben, legend, lemon, Lenin, lessen, lesson, Marion, melon, parent, peasant, Pelham, penance, pennant, pheasant, pleasant, Plenum, preference, presence, present, pression, Preston, question, reckon, reddened, reference, resin, Reverend, second, serfdom, session, seven, Sharon, Stephens, tenant, Terence, threaten, variance, variant, vellum, venom, veteran, weapon, weren, Weston
3 Syllables: SUU
3 Syllables: USU
aberrant, accession, aggression, agrarian, apparent, aquarium, assessment, barbarian, Bavarian, Bulgarian, compression, concession, confession, contestants, depression, digression, discretion, expression, fluorescent, forbearance, grammarian, Hungarian, impairment, impression, incessant, inherent, interment, intestine, investment, librarian, Lieutenant, Magellan, obsession, oppression, ovarian, possession, predestined, preferment, procession, profession, progression, quiescence, quiescent, quintessence, recession, regression, repellent, repression, secession, sectarian, succession, suppression, transgression, transparent, unpleasant
4 Syllables: UUSU
acquiescence, adolescence, adolescent, antiquarian, cerebellum, convalescence, convalescent, effervescence, evanescent, incandescent, indiscretion, intercession, iridescent, Mahometan, obsolescence, omnipresence, omnipresent, phosphorescent, prepossessions, proletarian, retrogression, Unitarian, vegetarian
5 Syllables: UUUSU
Found 172 words across 5 groupings. Skipped 57 excess words of a similar stem.