irradiation

noun

1. (uncountable)An act of irradiating, or state of being irradiated.
2. (countable, uncountable)An act of irradiating, or state of being irradiated.
3. (countable, obsolete, uncountable)illumination; irradiance; brilliance.
4. (countable, figuratively, obsolete, uncountable)mental light or illumination.
5. (countable, obsolete, uncountable)The apparent enlargement of a bright object seen upon a dark ground, due to the fact that the portions of the retina around the image are stimulated by the intense light; as when a dark spot on a white ground appears smaller, or a white spot on a dark ground larger, than it really is, especially when a little out of focus.