thistle (n.)youdaoicibaDictYouDict[thistle 词源字典]
prickly herbaceous plant, Old English þistel, from Proto-Germanic *thistilaz (cognates: Old Saxon thistil, Old High German distil, German Distel, Old Norse þistell, Danish tidsel), of uncertain origin; perhaps from an extended form of PIE root *steig- "to prick, stick, pierce." Emblematic of Scotland since 15c.[thistle etymology, thistle origin, 英语词源]