horse cart vs horse-cart

horse cart and horse-cart both are nouns.

Word	Noun	Adjective	Verb	Adverb
horse cart	Yes	No	No	No
horse-cart	Yes	No	No	No

As nouns, horse cart and horse-cart are synonyms defined as:

horse cart and horse-cart: heavy cart; drawn by a horse; used for farm work

horse cart (noun)	horse-cart (noun)
heavy cart; drawn by a horse; used for farm work	heavy cart; drawn by a horse; used for farm work