coat vs outer garment

coat and outer garment both are nouns.

Word	Noun	Adjective	Verb	Adverb
coat	Yes	No	Yes	No
outer garment	Yes	No	No	No

As nouns, outer garment is a hypernym of coat; that is, outer garment is a word with a broader meaning than coat:

coat: an outer garment that has sleeves and covers the body from shoulder down; worn outdoors
outer garment: a garment worn over other garments

Other hypernyms of coat include overgarment.

coat (noun)	outer garment (noun)
growth of hair or wool or fur covering the body of an animal	a garment worn over other garments
an outer garment that has sleeves and covers the body from shoulder down; worn outdoors
a thin layer covering something

coat (verb)	outer garment (verb)
cover or provide with a coat
put a coat on; cover the surface of; furnish with a surface
form a coat over