1 Syllable: S
2 Syllables: SU
7, Aaron, arid, Baron, barren, beckon, Bedlam, bellum, breasted, Bremen, brethren, Breton, carriage, cession, cherub, Clarence, Clemens, Clement, crescent, currant, deaden, deference, Devon, dresses, ebbed, edges, Edmond, Edmund, Edwin, Ellen, Epsom, errand, errant, Essen, essence, Evan, extant, felon, fetid, freshened, harem, headed, heaven, Helen, Herod, heron, Hessian, Karen, leaden, leaven, Leben, legend, lemon, Lenin, lessen, lesson, leverage, melon, message, method, nested, parent, peasant, Pelham, penance, pennant, petted, pheasant, pleasant, Plenum, preference, pregnant, presence, present, presses, pression, Preston, question, reckon, rectum, reddened, reference, requiem, resin, rested, Reverend, second, section, segment, septum, session, seven, sexton, Sharon, sketches, spectrum, Stephens, stresses, stretches, tenant, Terence, terras, threaded, threaten, vellum, venom, veteran, weapon, wedded, wedges, weren, Weston, wreckage
3 Syllables: SUU
3 Syllables: USU
aberrant, acceptance, accession, affection, aggression, apparent, arrested, assessment, collection, complexion, compression, conception, concession, confession, congested, connection, connexion, contestants, contested, convection, correction, deception, defection, deflection, dejection, depresses, depression, detection, digression, dilemmas, direction, discretion, ejection, election, erection, exception, expectant, expresses, expression, fluorescent, forbearance, impression, inception, incessant, infection, inflection, inherent, injection, inspection, intestine, intrepid, invested, investment, Lieutenant, Magellan, miscarriage, objection, obsession, oppression, percentage, perception, perfection, possesses, possession, predestined, presented, procession, profession, progression, projection, protection, quiescence, quiescent, quintessence, reception, recession, reflection, reflexion, regression, rejection, relented, repellent, repression, requested, resented, secession, selection, subjection, successes, succession, suggested, suppression, transgression, transparent, umbrellas, unpleasant
4 Syllables: UUSU
acquiescence, adolescence, adolescent, cerebellum, circumspection, convalescence, convalescent, disaffection, effervescence, evanescent, imperfection, incandescent, indiscretion, insurrection, intercession, interregnum, intersection, introspection, iridescent, Mahometan, misconception, obsolescence, omnipresence, omnipresent, phosphorescent, preconceptions, predilection, prepossessions, recollection, reelection, represented, resurrection, retrogression
Found 250 words across 5 groupings. Skipped 83 excess words of a similar stem.