tub-cart vs donkey cart

tub-cart and donkey cart both are nouns.

Word	Noun	Adjective	Verb	Adverb
tub-cart	Yes	No	No	No
donkey cart	Yes	No	No	No

As nouns, tub-cart and donkey cart are synonyms defined as:

Other synonyms of tub-cart include pony cart, ponycart.

tub-cart (noun)	donkey cart (noun)
a cart with an underslung axle and two seats	a cart with an underslung axle and two seats