CERN

The name CERN is derived from the acronym for the French "Conseil Européen pour la Recherche Nucléaire", or European Council for Nuclear Research, a provisional body founded in 1952 with the mandate of establishing a world-class fundamental physics research organization in Europe. At that time, pure physics research concentrated on understanding the inside of the atom, hence the word "nuclear".

The official name of the organization following its establishment is the European Organization for Nuclear Research (English) and Organisation européenne pour la recherche nucléaire (French).

For more information, see Wikipedia and the CERN website.