nuclear

{ } a. 1. Of or pertaining to a nucleus; as, the nuclear spindle (see Illust. of Karyokinesis) or the nuclear fibrils of a cell; the nuclear part of a comet, etc. [ 1913 Webster ]

n. an explosive device, whether used as a weapon or for other purposes, which depends for most of its explosive power on the release of energy from within atomic nuclei. A fission device or a fusion device. [ PJC ]

n. Energy derived from nuclear reactions; -- used at present especially of electrical power generated in atomic reactors, but encompassing also fusion energy.
Syn. -- atomic energy, atomic power, nuclear energy, nuclear power. [ WordNet 1.5 ]

n. The branch of engineering concerned with the design and construction and operation of nuclear reactors. [ WordNet 1.5 ]

n. The explosion of an atomic bomb or atomic device; -- sometimes also used of fusion-powered explosions.
Syn. -- atomic explosion. [ WordNet 1.5 ]

n. A family consisting of parents and their children and grandparents of a marital partner. [ WordNet 1.5 ]

n. A nuclear reaction in which a heavy atomic nucleus splits into smaller nuclei with the simultaneous release of energy.
Syn. -- fission. [ WordNet 1.5 ]

n. A type of nuclear reaction in which atomic nuclei combine to form more massive nuclei with the simultaneous release of energy. Syn. -- fusion, nuclear fusion reaction. [ WordNet 1.5 ]