Radiation scattering

In telecommunication, radiation scattering is the diversion of radiation (thermal, electromagnetic, or nuclear) from its original path as a result of interaction or collisions with atoms, molecules, or larger particles in the atmosphere or other media between the source of radiation (e.g., a nuclear explosion) and a point some distance away. As a result of scattering, radiation (especially gamma rays and neutrons) will be received at such a point from many directions instead of only from the direction of the source.

Source: from Federal Standard 1037C and from the Department of Defense Dictionary of Military and Associated Terms