pectoralis vs musculus pectoralis

pectoralis and musculus pectoralis both are nouns.

Word	Noun	Adjective	Verb	Adverb
pectoralis	Yes	No	No	No
musculus pectoralis	Yes	No	No	No

As nouns, pectoralis and musculus pectoralis are synonyms defined as:

pectoralis and musculus pectoralis: either of two large muscles of the chest

Other synonyms of pectoralis include pecs, pectoral, pectoral muscle.

pectoralis (noun)	musculus pectoralis (noun)
either of two large muscles of the chest	either of two large muscles of the chest