irradiation Definition

1. medicine.
Exposure of part of the body to electromagnetic radiation or a radioactive source, for diagnostic or therapeutic purposes.
2. optics.
An optical illusion that causes bright objects to appear larger than their actual size when viewed against a dark background.
3. A method of preserving food by exposing it to either ultraviolet radiation or ionizing radiation from radioactive isotopes.
4. The use of microwaves to heat food.