The term “Holocaust” most commonly refers to the systematic, state‑sponsored persecution and murder of approximately six million Jews, along with millions of other victims, by Nazi Germany and its collaborators during World War II.

Basic meaning

  • In modern history, the Holocaust (capital H) means the Nazi genocide of Europe’s Jews between 1933 and 1945, carried out through ghettos, shootings, concentration and extermination camps.
  • Many scholars emphasize that it was a planned, bureaucratic, and industrialized attempt to annihilate the Jewish people, while also targeting Roma, people with disabilities, and others.

Origin of the word

  • The word holocaust comes from Greek roots meaning “wholly burned” or “sacrifice by fire,” originally used for burnt offerings in ancient religious contexts.
  • In English before the 20th century, it could more generally mean a large destruction by fire or mass slaughter , but this usage is now overshadowed by its association with the Nazi genocide.

Capital “H” vs lowercase

  • Holocaust (capitalized) almost always refers specifically to the Nazi genocide during World War II.
  • holocaust (lowercase) can still mean a vast destruction or massacre (for example “a nuclear holocaust”), but many people avoid using it casually out of respect and to prevent confusion with the historical event.

Related terms you might see

  • Shoah : A Hebrew word meaning “catastrophe,” widely used, especially in Israel and among scholars, to refer to the same event; some prefer it because it avoids the sacrificial or religious overtones of the word “Holocaust.”
  • Genocide : A legal and historical term meaning the intent to destroy, in whole or in part, a national, ethnic, racial, or religious group; the Holocaust is one of the defining examples of genocide.

TL;DR:
“Holocaust” today primarily means the Nazi genocide of six million Jews and millions of other victims during World War II; the word itself comes from Greek for “wholly burned,” but its historical meaning now strongly dominates.

Information gathered from public forums or data available on the internet and portrayed here.