Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
multi-billionaire is a noun meaning "a very rich person whose material wealth is valued at many billions of dollars". It carries one recorded sense.
a very rich person whose material wealth is valued at many billions of dollars
Definitions, synonyms and semantic relations for multi-billionaire come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.