irradiation

(medicine) the treatment of disease (especially cancer) by exposure to a radioactive substance

(Pavolvian conditioning) the elicitation of a conditioned response by stimulation similar but not identical to the original stimulus

the apparent enlargement of a bright object when viewed against a dark background

(physiology) the spread of sensory neural impulses in the cortex

a column of light (as from a beacon)

the condition of being exposed to radiation