- black catechu, catechu - extract of the heartwood of Acacia catechu used for dying and tanning and preserving fishnets and sails; formerly used medicinally
--1 is a kind of infusion, extract
--1 is a substance of catechu, Jerusalem thorn, Acacia catechu - catechu, Jerusalem thorn, Acacia catechu - East Indian spiny tree having twice-pinnate leaves and yellow flowers followed by flat pods; source of black catechu
--2 is a kind of acacia
--2 is a member of genus Acacia
--2 has substances: black catechu, catechu