[¦ep·ə′thər·məl ′nü‚trän] (nucleonics) A neutron having an energy in the range immediately above the thermal range, roughly between 0.02 and 100 electronvolts.
epithermal neutron
ep·i·ther·mal neu·tron
a neutron having an energy in the range immediately above the thermal range, that is, having an energy between a few hundredths and approximately 100 ev.