Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
interposition is a noun meaning "the action of interjecting or interposing an action or remark that interrupts". It carries 2 recorded senses.
the action of interjecting or interposing an action or remark that interrupts
the act or fact of interposing one thing between or among others
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for interposition come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.