柯林斯詞典tannin /?t?n?n/ 1. N-UNCOUNT Tannin is a yellow or brown chemical that is found in plants such as tea. It is used in the process of making leather and in dyeing. 丹寧酸 返回 tannin劍橋詞典(one of) a group of chemicals that are found in plant cells , especially in leaves , bark (= a tree's outer covering ), and fruit that is not yet ready to eat 丹寧（酸），鞣酸 返回 tannin