n.

any object that radiates energy

heater consisting of a series of pipes for circulating steam or hot water to heat rooms or buildings

a mechanism consisting of a metal honeycomb through which hot fluids circulate; heat is transferred from the fluid through the honeycomb to the airstream that is created either by the motion of the vehicle or by a fan

Theory of Focusing Radiators
Scalable liquid cooling system with modular radiators
Mutual Acoustic Impedance between Radiators in an Infinite Rigid Plane
Design of tungsten complex gratings for thermophotovoltaic radiators
Enhanced Dipole-Dipole Interaction between Elementary Radiators Near a Surface
Thermophotovoltaic generation with selective radiators based on tungsten surface gratings
Multiband Handset Antenna With a Parallel Excitation of PIFA and Slot Radiators
The Field and Radiation Impedance of Mechanical Radiators on the Free Surface of a Semi-Infinite Isotropic Solid
Modal sensing of efficient acoustic radiators with polyvinylidene fluoride distributed sensors in active structural acoustic control...
Experimental study of heat transfer enhancement using water/ethylene glycol based nanofluids as a new coolant for car radiators ☆