Kosher

google

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mid 19th century: from Hebrew kāšēr ‘proper’.

wiktionary

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From Yiddish כּשר‎ (kosher), from Hebrew כָּשֵׁר‎ (kashér).

etymonline

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kosher (adj.)

"ritually fit or pure, clean, lawful, conforming to the requirements of the Talmud" (especially of food), 1850, in early use also kasher, coshar, from Yiddish kosher, from Hebrew kasher "fit, proper, lawful," from base of kasher "was suitable, proper." Generalized sense of "correct, legitimate" is from 1896.