Answer: catechus

AnswerCrossword Clue
catechusany of several astringent substances obtained from various tropical plants, esp. from the wood of two East Indian acacias, Acacia catechu and A. suma: used in medicine, dyeing, tanning, etc.
catechusCATECHU, a resin used in tanning, also CACHOU, CASHOO, CUTCH, KUTCH