What is Sumach?
Sumach definition and meaning on Dictionary terms:
any of several shrubs or small trees belonging to the genus Rhus of the cashew family, having milky sap, compound leaves, and small, fleshy fruit.
a preparation of the dried and powdered leaves, bark, etc., of certain species of Rhus, especially R. coriaria of southern Europe, used especially in tanning.
the wood of these trees.