madder (n.)youdaoicibaDictYouDict[madder 词源字典]
type of plant (in modern use Rubia tinctorum) used for making dyes, Old English mædere, from PIE *modhro- "dye plant" (cognates: Old Norse maðra, Old High German matara "madder," Polish modry, Czech modry "blue").[madder etymology, madder origin, 英语词源]