köken: From Middle High German distel, from Old High German distil, from Proto-West Germanic *þistil, from Proto-Germanic *þistilaz, which see for cognates. The alternative long-vowel pronunciation is based on Middle Low German dîstel (alongside distel), whose length is unexplained (cf. the same in Middle Dutch diestel, Early Modern Dutch dijstel).
köken: From late Latin cardō, cardōnis (“thistle”) (unrelated to Classical Latin cardō, cardinis (“a hinge”)), derived from Latin carduus. Doublet of cardon.
köken: Probably an ancient Aramaic borrowing, given that widespread Northeastern Neo-Aramaic ܩܰܠܩܳܐ (qalqa, “cardoon”) has another widespread variant ܩܰܩܢܳܐ (qaqna). For ܩ (q) giving ک (k) see کما (komâ, “Ferula”), for the ر (r) شنار (šenâr, “swimming; horehound”) in place of شنا (šenâ), though trailing extension of a root by ر (r) within Semitic is also very often observed, so either way a match is…
köken: Possibly from Proto-Indo-European *kers- (“to scratch, scrape, rub, card”), cognate with Middle Low German harsch (“hairy”), Russian короста (korosta, “scab”), Old Church Slavonic краста (krasta), Lithuanian karsiu (“to comb”). This root may itself be a metathesis of *kes-r-, *kser- (cf. *ksen-), from *kes-.
köken: Cognate with Latvian usna (“thistle”) and probably with dialectal Proto-Slavic *ušь (“carduoid”) (whence Old East Slavic оушь (ušĭ)), for Proto-Balto-Slavic [Term?] (“thistle”). Further origin uncertain. Possibly derived from the oblique ablaut-grade of Proto-Indo-European *wósHr̥ ~ *usHén-, whence Sanskrit उष्ण (uṣṇa, “onion”), Latin ūniō (“onion”).