carmaker vs automaker

carmaker and automaker both are nouns.

Word	Noun	Adjective	Verb	Adverb
carmaker	Yes	No	No	No
automaker	Yes	No	No	No

As nouns, carmaker and automaker are synonyms defined as:

carmaker and automaker: a business engaged in the manufacture of automobiles

Other synonyms of carmaker include auto maker, auto manufacturer, car maker, car manufacturer.

carmaker (noun)	automaker (noun)
a business engaged in the manufacture of automobiles	a business engaged in the manufacture of automobiles