fission fungi pl.n.
- Fission-fusion bomb
noun 1. another name for fusion bomb
- Fission product
noun 1. a nuclide produced either directly by nuclear fission or by the radioactive decay of such a nuclide fission product n. A usually radioactive isotope produced as a result of the fission of a massive atom such as U235.
- Fission reactor
noun 1. a nuclear reactor in which a fission reaction takes place
- Fission track
fission track A track left by the decay of uranium atoms in a mineral. By analyzing the number and nature of these tracks in a sample mineral and inducing further fission of the remaining uranium by irradiation with neutrons to create new tracks for comparison, one can estimate the approximate age of the sample.