| Catechuic | a. Of or pertaining to catechu or its derivatives. See catechin. [ 1913 Webster ] |
| Protocatechuic | a. (Chem.) Pertaining to, derived from, or designating, an organic acid which is obtained as a white crystalline substance from catechin, asafetida, oil of cloves, etc., and by distillation itself yields pyrocatechin. [ 1913 Webster ] |