auto-mechanic vs grease monkey

auto-mechanic and grease monkey both are nouns.

Word	Noun	Adjective	Verb	Adverb
auto-mechanic	Yes	No	No	No
grease monkey	Yes	No	No	No

As nouns, auto-mechanic and grease monkey are synonyms defined as:

auto-mechanic and grease monkey: someone whose occupation is repairing and maintaining automobiles

Other synonyms of auto-mechanic include automobile mechanic, car-mechanic, mechanic.

auto-mechanic (noun)	grease monkey (noun)
someone whose occupation is repairing and maintaining automobiles	someone whose occupation is repairing and maintaining automobiles