In honour of Chinese New Year, let us look at a word whose origins are, surprisingly, Chinese: ketchup.
In Chinese dialect, k'e-chap meant “brine of pickled fish” (probably disgusting on french fries). Around 1700, the British discovered this condiment: a pickled sauce including anchovies or oysters, mushrooms and walnuts, but no tomatoes were involved, for they were expensive and besides viewed as a suspicious American import by the English till the late 1800s. "Ketchup", to Jonathan Swift, Byron, and Dickens (among the many great names in English literature who have felt the need to mention it) was probably more like Worcestershire sauce.
In 1876, Heinz, needing to find a way to preserve the notoriously perishable fruit which by then the US was producing in large quantities, started using the word “ketchup” for a sweetish pureed pickle of tomatoes.
The form "catsup" evolved out of "catchup", which is the earliest form for which we have evidence in English. For a while, "catchup/catsup" and "ketchup" were in contention on both sides of the language, but "ketchup" quickly won out in Britain while both forms survived in the US. "Catsup", however, which in the mid-20th century was the favoured form in the US, has definitely been on the wane since about 1970, as this Google ngram shows.
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