noun: Initialism of National Broadcasting Company: U.S. television and radio network.
noun: (historical) Abbreviation of National Biscuit Company: U.S. food company, now Nabisco.
noun: (weaponry) Abbreviation of nuclear weapon, biological weapon and chemical weapon. [A weapon that derives its energy from the nuclear reactions of either fission or fusion.]
adjective: (weaponry) Abbreviation of nuclear, biological, chemical. [Pertaining to the nucleus of an atom.]