2 syllables:
beatson, beats in, meets in, seats in, sheets in, streets in, ve tsin

3 syllables:
defeats in, elites in, lauritsen, receipts in

2 syllables:
frisian, fission, grison, lycian, frisson, listen, titian, stiffen, griffon, vision, driven, whitsun, christen, glisten, mission, writhen, sivan, given, gryphon, grecian, heathen, leeson, lesion, pleven, reason, season, stephen, steven, treason, wesun

3 syllables:
prevision, position, admission, tahitian, vendition, tradition, ignition, collision, sedition, decision, perdition, monition, excision, rescission, magician, fruition, ambition, forgiven, emission, tuition, technician, precision, contrition, condition, transition, addition, envision, mortician, edition, optician, rendition, incision, remission, volition, clinician, audition, transmission, patrician, cognition, submission, physician, provision, revision, elysian, derision, sortition, logician, petition, abscission, partition, omission, division, elision, commission, attrition, musician, nutrition, munition, night vision, suspicion, galician, parisian, detrition, tactician, permission, accretion, adhesion, artesian, cohesion, completion, concretion, deletion, depletion, dioecian, dry season, excretion, high treason, mauritian, partizan, phoenician, preseason, repletion, salishan, secretion, tunisian, uneven, unreason, venetian, with reason

4 syllables:
saurischian, deglutition, in condition, dietitian, inhibition, apposition, ammunition, imposition, ornithischian, composition, malnutrition, cell division, imbibition, coalition, field emission, exhibition, premonition, intromission, long division, parturition, intermission, esthetician, repetition, micturition, acquisition, house physician, erudition, cosmetician, postposition, ordovician, prohibition, trade edition, imprecision, politician, brussels griffon, demolition, indecision, definition, supervision, obstetrician, short division, rhetorician, dietician, competition, preterition, readmission, reposition, phase transition, manumission, admonition, extradition, preposition, superstition, inanition, inquisition, recondition, electrician, aesthetician, requisition, expedition, disquisition, deposition, proposition, circumcision, transposition, recognition, precondition, apparition, supposition, statistician, precognition, malposition, split decision, phonetician, streptolysin, abolition, exposition, opposition, disposition, intuition, age of reason, austronesian, baseball season, fishing season, football season, for some reason, growing season, hockey season, holstein-friesian, hunting season, indonesian, in due season, pass completion, polynesian, rainy season, salt depletion, silly season, social season, subartesian, within reason, with more reason

5 syllables:
juxtaposition, mathematician, dialectician, photoemission, lotus position, geriatrician, decomposition, predisposition, indisposition, dental technician, academician, presupposition, pediatrician, semiotician, paediatrician, geometrician, redefinition, interposition, theoretician, arithmetician, nuclear fission, basketball season, elizabethan, mucous secretion, with greater reason

6 syllables:
boundary condition, econometrician, limited edition, reduction division, resident physician, writ of prohibition, exhibition season, internal secretion, theatrical season

7 syllables:
double decomposition, automatic transmission, missionary position, electrodeposition, secondary emission, malayo-polynesian

8 syllables:
reciprocal inhibition

9 syllables:
atomic energy commission