fission /ˈfɪʃən/noun 3verb 2forms 3 noun3 •The process whereby one item splits to become two. •nuclear fission: The process of splitting the nucleus of an atom into smaller particles. •The process by which a bacterium splits to form two daughter cells. verb2 •To cause to undergo fission. •To undergo fission. formsfissioned · fissioning · fissions
