Nuclear describes something that has to do with the nucleus — the central part — of an atom. If you're a nuclear physicist, you do a lot of work with that part of the atom.
Nuclear power, which comes from nuclear fission — the energy released when the nucleus of an atom is split — is a controversial source of renewable energy. The word nuclear is sometimes used broadly to refer to the core of something. Your nuclear family is you, your parents, and your siblings — in a sense, the central part of your world, kind of like the nucleus of an atom.
Close your vocabulary gaps with personalized learning that focuses on teaching the words you need to know.