From the Greek: "holos" (completely) and "kaustos" (burned sacrificial offering).

Hello,

Just for info:

Holocaust can mean:

The Holocaust, or Shoah, the systematic killing mainly of six million Jews, but also of Gypsies, Slavs, homosexuals and other "undesirable" groups in Europe during World War II. Since 1978, this has been the main meaning of the English term.

holocaust (sacrifice), a burnt offering, from Greek holo-kauston "all burnt". The original sense, referring to a completely-burnt sacrifice
By extension the word was used in English to refer to other acts of obliteration by burning (or massacres in general).

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