Word Study
catechu
CIDE DICTIONARY
catechu, n. [See Cashoo.].
A dry, brown, astringent extract, obtained by decoction and evaporation from the Acacia catechu , and several other plants growing in India. It contains a large portion of tannin or tannic acid, and is used in medicine and in the arts. It is also known by the names terra japonica , cutch , gambier , etc. Ure. Dunglison. [1913 Webster]
OXFORD DICTIONARY
catechu, n. (also cachou) gambier or similar vegetable extract, containing tannin.
Etymology
mod.L f. Malay kachu
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