Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
mandator is a noun meaning "an authority who issues a mandate". It carries one recorded sense.
an authority who issues a mandate
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 mandator come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.