Ketchup is a spiced sauce used for its condimental effect in imparting
flavor, or to give relish to other foods. It receives its distinctive
name from the base used, as, tomato, grape, currant, mushroom, walnut,
etc.
The terms ketchup, catchup, and catsup are used to designate any spiced
sauce and seemingly without any reason for the one used other than
personal preference. Though the derivation of the term has been
attributed to different sources by the dictionaries, there seems to be
more reason for the use of the term ketchup than for the others, both
upon the ground of its prior and more general use, and from the history
of its derivation. Murray[1] gives the derivation of ketchup from the
Amoy dialect of the Chinese, the term being =koechiap= or =ke-tsiap=,
meaning a brine of pickled fish or shell fish; and he states that the
Malayan =kechap=, which has been claimed as the original source, may be
from the Chinese, but that the word =kitjap=, as given by some
dictionaries from the Japanese, is an impossible word for that language,
and is possibly an error for Javanese. The term catchup given by some
dictionaries appears to be based on the assumption that the first
syllable ketch is a colloquial form of catch. Many manufacturers use the
word catsup, a spelling for which there seems to be no etymological
warrant. The earliest use of the term catsup, found by the writer, with
any particular significance attached to it as distinct from the other
two terms, is by Kitchiner, an English physician, in the Cook’s Oracle,
in which directions are given for reducing “catchup” to half the
quantity, the statement being that “it may then be called double cat-sup
or dog-sup.” The first edition of the book appeared in 1817 in England.
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Footnote 1:
Murray, J. A. H. New English Dictionary.