Morin \Mo"rin\, n. (Chem.) A yellow crystalline substance ({C15H10O7}) of acid properties extracted from fustic ({Chlorophora tinctoria} syn. {Maclura tinctoria}, formerly called {Morus tinctoria}); -- called also {moric acid} and {natural yellow 8}. It is used as a dye for wool, giving a color from lemon yellow through olive to olive brown, depending on the metal with which it is mordanted. [1913 Webster +PJC]