carriage dog vs coach dog

carriage dog and coach dog both are nouns.

Word	Noun	Adjective	Verb	Adverb
carriage dog	Yes	No	No	No
coach dog	Yes	No	No	No

As nouns, carriage dog and coach dog are synonyms defined as:

carriage dog and coach dog: a large breed having a smooth white coat with black or brown spots; originated in Dalmatia

Other synonyms of carriage dog include dalmatian.

carriage dog (noun)	coach dog (noun)
a large breed having a smooth white coat with black or brown spots; originated in Dalmatia	a large breed having a smooth white coat with black or brown spots; originated in Dalmatia