2 syllables:
isms, prisms, schisms

3 syllables:
baptisms, grecisms, sophisms, yogiisms

4 syllables:
aneurisms, anglicisms, aphorisms, asterisms, barbarisms, briticisms, britishisms, catechisms, communism's, communisms, criticisms, cynicisms, dandyisms, despotisms, dualisms, dysphemisms, egotisms, embolisms, euphemisms, euphuisms, exorcisms, formalisms, gallicisms, germanisms, hypnotism's, journalism's, judaism's, latinisms, legalisms, liberalism's, localisms, mannerisms, mechanisms, methodisms, mysticisms, organism's, organisms, plagiarisms, putinisms, ruralisms, solecisms, specialisms, spoonerisms, syllogisms, symbolisms, syncretisms, traumatisms, verbalisms, vocalisms, vulgarisms, witticisms

5 syllables:
africanisms, anachronisms, animalisms, antagonisms, australianisms, automatisms, capitalism's, conservatisms, fanaticisms, hypocorisms, indianisms, initialisms, malapropisms, metabolisms, mutualisms, neologisms, parallelisms, protologisms, provincialisms, puritanisms, radicalisms, surrealism's, surrealisms

6 syllables:
americanisms, canadianisms, colloquialisms, fundamentalisms, largest organisms, microorganisms, servomechanisms

7 syllables:
photoperiodisms