Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
world-shattering is an adjective meaning "sufficiently significant to affect the whole world". It carries one recorded sense.
sufficiently significant to affect the whole world
“earthshaking proposals”
“the contest was no world-shaking affair”
“the conversation...could hardly be called world-shattering”
Definitions, synonyms and semantic relations for world-shattering come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.