köken: From Middle High German bœse, bōse, from Old High German bōsi, from Proto-West Germanic *bausī, from Proto-Germanic *bausuz (“inflated, puffed up, arrogant, bad”), from Proto-Indo-European *bʰew-, *bew- (“to blow, inflate, swell”), akin to Yiddish בייז (beyz), Dutch boos, and English boast.
köken: Inherited from Old Anatolian Turkish دلو (delü), from Proto-Turkic *tēlbe (“mad, stupid”). Cognate with Turkish deli, Uzbek telba, Turkmen däli and telbe, Southern Altai тели (teli), Tatar тилбә (tilbä, “foolish person”), Chuvash тилӗр (tilĕr, “become enraged”) etc.
mad, crazy, insane, lunatic, bonkers, not sane, exhibiting unsoundness or disorder of mind, mentally deranged · whimsical, eccentric, quirky, bizarre, odd, given to quirks or idiosyncrasies, strange in a somewhat silly, manner · inconsiderate, thoughtless, unthoughtful, not considerate, showing lack of due thought or care for the other people
çekim: karşılaştırma däliräk · üstünlük iň däli
köken: From Proto-Turkic *tēlbe (“mad, crazy”). Cognate with Turkish deli, Azerbaijani dəli, Bashkir тиле (tile), Kazakh дәлду (däldu), Kyrgyz тели (teli), Uyghur تەلۋە (telwe) and Uzbek telba.
madman, lunatic · madness, insanity · enthusiast, fan
eş: 狂人, きじるし, ばか, マニア, フリーク
köken: Verbal noun of 気(き)が違(ちが)う (ki ga chigau, “to be mad”). Analyzable as 気(き) (ki, “mind, temperament, character; mood, spirit”) + 違(ちが)い (chigai, “difference; mistake”, 連(れん)用(よう)形(けい) (ren'yōkei, “stem or continuative form”) of the verb 違(ちが)う (chigau, “to differ; to be mistaken”)).
köken: From Old Swedish dāre, from Old Norse dári, Middle Low German dore, from Old Saxon *dōro, from Proto-West Germanic *dauʀō. See also German Tor; Icelandic dári, Danish dåre.
çekim: karşılaştırma bolondabb · üstünlük legbolondabb
köken: Borrowed from a Slavic language. Compare Polish błąd (“mistake”), Russian блуд (blud, “fornication”), from Proto-Slavic *blǫdъ. Compare also unrelated German blöd.
From Byzantine Greek τρελός (trelós), from Koine Greek τρηρός (trērós), from Ancient Greek τρήρων (trḗrōn). The chess sense is a semantic loan from French fou.