tomato ketchup vs catsup

tomato ketchup and catsup both are nouns.

Word	Noun	Adjective	Verb	Adverb
tomato ketchup	Yes	No	No	No
catsup	Yes	No	No	No

As nouns, tomato ketchup and catsup are synonyms defined as:

Other synonyms of tomato ketchup include cetchup, ketchup.

tomato ketchup (noun)	catsup (noun)
thick spicy sauce made from tomatoes	thick spicy sauce made from tomatoes