cat·e·chu 
(kătə-ch′)
(kătə-ch′)n.
1. A spiny Asian tree (Acacia catechu) having bipinnately compound leaves, spikes of yellow flowers, and dark heartwood.
2. A raw material obtained from the heartwood of this plant, used in the preparation of tannins and brown dyes. In both senses also called cutch.
[Probably from Malay kachu, probably from Dravidian karaiyal, karaiccal, that which is dissolved, from karai, to melt.]