Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
most-valuable is an adjective meaning "designating the player judged to be the most important to the sport". It carries one recorded sense.
designating the player judged to be the most important to the sport
“the most-valuable player award”
sport
Definitions, synonyms and semantic relations for most-valuable come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.