2 syllables:
fissions, lycians, mission's, missions

3 syllables:
logicians, additions, admissions, ambitions, auditions, beauticians, clinicians, cognitions, commission's, commissions, conditions, demissions, edition's, editions, emissions, galicians, ignitions, magicians, monitions, morticians, munitions, musician's, musicians, musicians', omissions, opticians, partitions, patricians, permissions, petitions, physician's, physicians, physicians', positions, possitions, remissions, renditions, seditions, submissions, suspicions, tacticians, technician's, technicians, traditions, transitions, transmissions, tuitions, volitions

4 syllables:
abolitions, acousticians, acquisition's, acquisitions, admonitions, aestheticians, air-conditions, airconditions, ammunitions, apparitions, appositions, coalition's, coalitions, competition's, competitions, compositions, cosmeticians, decommissions, definitions, demolitions, depositions, dieticians, dietitian's, dietitians, dispositions, disquisitions, ebullitions, electricians, electricians', estheticians, exhibitions, expeditions, expositions, extraditions, imbibitions, impositions, inhibitions, inquisitions, intermissions, intuitions, laodiceans, linguisticians, manumissions, mechanicians, noise conditions, obstetricians, opposition's, oppositions, phoneticians, politician's, politicians, politicians', precognitions, preconditions, prepositions, prohibition's, prohibitions, propositions, recognition's, recognitions, reconditions, repartitions, repetitions, repositions, requisitions, retransmissions, rhetoricians, samogitians, ski conditions, statisticians, submunitions, superstitions, suppositions, transpositions

5 syllables:
academicians, arithmeticians, biometricians, cliometricians, contrapositions, cyberneticians, decompositions, diagnosticians, dialecticians, geometricians, geriatricians, indispositions, interpositions, juxtapositions, mathematicians, metaphysicians, neurotransmissions, paediatricians, pediatricians, predispositions, presuppositions, redefinitions, semioticians, superpositions, theoreticians, weather conditions

6 syllables:
basketball positions, bezos expeditions, econometricians, superimpositions, windows 10 editions

7 syllables:
list of apollo missions, list of murdered musicians

8 syllables:
iatromathematicians, thermosetting compositions

9 syllables:
american football positions

10 syllables:
meteorological conditions

2 syllables:
listens, prisons, rhythms, visions

3 syllables:
provisions, collisions, decisions, divisions, revisions