Word Study
ketchup
CIDE DICTIONARY
ketchup, n. [Probably of East Indian origin, because it was originally a kind of East Indian pickles. Cf. also Malay k fish sauce. MW10 .].
A pureed table sauce made predominantly from tomatoes, flavored with onions, sugar, salt and spices; called also tomato ketchup . The term is also applied to pureed sauces containing mushrooms, walnuts, etc., being called in such cases mushroom ketchup , walnut ketchup , etc. [PJC]
OXFORD DICTIONARY
ketchup, n. (also catchup) a spicy sauce made from tomatoes, mushrooms, vinegar, etc., used as a condiment.
Etymology
Chin. dial. koechiap pickled-fish brine
For further exploring for "ketchup" in Webster Dictionary Online