(obsolete) 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.
(uncountable) a process of sterilisation whereby radiation is passed through a bag containing food, utensils, etc., to sterilise the contents.
“Following the nuclear accident, the ongoing irradiation of the surrounding area posed a severe threat to the health and safety of the local population.”
“The group charges that irradiation also deactivates the natural digestive enzymes found in raw food, and encourages fats to turn rancid.”
“Moreover, irradiation can destroy essential vitamins and nutrients that are naturally present in foods and can make food taste and smell rancid.”