blackbody radiation
n.— «The millimeter wave signature is also known as blackbody radiation and is made up of two properties: emissivity and reflectivity.» —“Brijot Imaging Systems, Inc. Delivers—with Passive Millimeter Wave Technology from Lockheed Martin—World’s First Commercial Real-Time Concealed Weapons Detection Camera” in Orlando, Fla. Business Wire Mar. 15, 2005. (source: Double-Tongued Dictionary)