serratus posterior vs musculus serratus posterior

serratus posterior and musculus serratus posterior both are nouns.

Word	Noun	Adjective	Verb	Adverb
serratus posterior	Yes	No	No	No
musculus serratus posterior	Yes	No	No	No

As nouns, serratus posterior and musculus serratus posterior are synonyms defined as:

serratus posterior and musculus serratus posterior: skeletal muscle that draws the rib cage backward and downward

Other synonyms of serratus posterior include posterior serratus muscle.

serratus posterior (noun)	musculus serratus posterior (noun)
skeletal muscle that draws the rib cage backward and downward	skeletal muscle that draws the rib cage backward and downward