nuclear fusion increases the mass through fusing two nuclei together into one
nuclear_fusion is nuclear_process. merging_of_cell_nuclei is biological_fusion. fusion is not nuclear_reaction. fusion_rocket is nuclear_rocket. fusion is nuclear_reaction. fusion_weapon is nuclear_weapon. nuclear_fusion is not nuclear_process. nuclear_fusion is not transformation_process. fusion_bomb is nuclear_weapon. nuclear_fusion is transformation_process.