car-mechanic vs automobile mechanic

car-mechanic and automobile mechanic both are nouns.

Word	Noun	Adjective	Verb	Adverb
car-mechanic	Yes	No	No	No
automobile mechanic	Yes	No	No	No

As nouns, car-mechanic and automobile mechanic are synonyms defined as:

car-mechanic and automobile mechanic: someone whose occupation is repairing and maintaining automobiles

Other synonyms of car-mechanic include auto-mechanic, grease monkey, mechanic.

car-mechanic (noun)	automobile mechanic (noun)
someone whose occupation is repairing and maintaining automobiles	someone whose occupation is repairing and maintaining automobiles