Cat"e*chu (?), n. [See Cashoo.] (Chem.) 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.