Catechu (/ˈkætɪʃuː/ or /ˈkætɪtʃuː/) isan extract of acacia trees used variously as a food additive, astringent, tannin, and dye. It is extracted from several species of Acacia, but especially Senegalia catechu (Acacia catechu), by boiling the wood in water and evaporating the resulting brew.
