Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
intramuscular is an adjective meaning "within a muscle". It carries one recorded sense.
within a muscle
“an intramuscular injection”
Definitions, synonyms and semantic relations for intramuscular come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.