radiation

Definitions

noun the process or state of spreading out in all directions from a central point
noun the waves of energy which are given off when heat is transferred
noun the waves of energy which are given off by a radioactive substance

The transmission of energy by electromagnetic means rather than by mechanical ones including conduction or convection. Electromagnetic Radiation is the more commonly-used term. In addition, emissions from radioactive decay are usually described as radiation even when they are generally viewed as particles (like alpha or beta particles) rather than waves.

The transmission of energy by means of electromagnetic waves of very long wave length. The energy travels in a straight line at the speed of light and is not affected by the temperature or currents of the air through which it passes.

The propagation of energy via electromagnetic waves, particle beams, sound, or the like, through a given medium such as space, the atmosphere, or a solid object. Also, the energy so propagated. Also, the process via which this occurs.
The energy associated with electromagnetic waves. This energy oscillates between its electric and magnetic components. electromagnetic radiation has both wavelike and particle-like properties. Also called electromagnetic radiation.
A stream of particles, such as electrons, neutrons, protons, or the like. Also, the emission of such particles. Also, the energy propagated via such particles.
The emission of particles or waves by a radioactive substance. Also, the particles or waves so emitted.
The exposure to radiation (1), radiation (2), radiation (3), or radiation (4).

noun waves of energy which are given off by some substances, especially radioactive substances

14 definitions in context