1. [A] Short name referring to investigation, study, and control of compromising emanations from information systems (IS) equipment. [INFOSEC-99] 2. To shield against compromising emanations.3. The unintentional radiation or conduction of compromising emanations from communications, non-communications and/or computer systems [CESG].See also: Radiation Security.4.The study and control of spurious electronic signals emitted from ADP equipment [TCSEC].TEMPEST is a standard for electromagnetic shielding for computer and communications equipment. It was created in response to the fact that information may be read from radiation from such devices at a distance.