Theres only been one true holocaust, and it was against the jews during WW2. All other genocides are called genocides because they dont meet the criteria for the definition of a holocaust.
Holocaust: to consume by fire
The jews were burned in ovens, therefore its called a holocaust. Get it?
Your reply was interesting, I had never heard it used in only that way. Nuclear holocaust was what those of us old enough often wondered about. But a reading of history shows that humans kill humans and what you call it in the end matters nada.
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n.
Great destruction resulting in the extensive loss of life, especially by fire.
Holocaust The genocide of European Jews and others by the Nazis during World War II: "Israel emerged from the Holocaust and is defined in relation to that catastrophe" (Emanuel Litvinoff).
A massive slaughter: "an important document in the so-far sketchy annals of the Cambodian holocaust" (Rod Nordland).
A sacrificial offering that is consumed entirely by flames.
[Middle English, burnt offering, from Old French holocauste, from Latin holocaustum, from Greek holokauston, from neuter of holokaustos, burnt whole : holo-, holo- + kaustos, burnt (from kaiein, to burn).]
holocaustal hol'o·caus'tal or hol'o·caus'tic adj.
USAGE NOTE Holocaust has a secure place in the language when it refers to the massive destruction of humans by other humans. Ninety-nine percent of the Usage Panel accepts the use of holocaust in the phrase nuclear holocaust. Sixty percent of the Panel accepts the sentence As many as two million people may have died in the holocaust that followed the Khmer Rouge takeover in Cambodia. But because of its associations with genocide, people may object to extended applications of holocaust. When the word is used to refer to death brought about by natural causes, the percentage of the Panel accepting drops sharply...."
holocaust: Definition from Answers.com