abdominal muscle vs abdominal

abdominal muscle and abdominal both are nouns.

Word	Noun	Adjective	Verb	Adverb
abdominal muscle	Yes	No	No	No
abdominal	Yes	Yes	No	No

As nouns, abdominal muscle and abdominal are synonyms defined as:

Other synonyms of abdominal muscle include ab.

abdominal muscle (noun)	abdominal (noun)
the muscles of the abdomen	the muscles of the abdomen

abdominal muscle (adjective)	abdominal (adjective)
	of or relating to or near the abdomen