1.  irradiation(n = noun.state) Array - the condition of being exposed to radiation; Array
is a kind of condition, status
Derived form verb irradiate₃

2.  irradiation(n = noun.phenomenon) beam, beam of light, light beam, ray, ray of light, shaft, shaft of light - a column of light (as from a beacon); Array
is a kind of light, visible light, visible radiation
has particulars: heat ray, high beam, moon-ray, moon ray, moonbeam, sunbeam, sunray, laser beam, low beam
Derived form verb irradiate₂

3.  irradiation(n = noun.event) Array - (physiology) the spread of sensory neural impulses in the cortex; Array
is a kind of spread, spreading

4.  irradiation(n = noun.cognition) Array - the apparent enlargement of a bright object when viewed against a dark background; Array
is a kind of illusion, semblance

5.  irradiation(n = noun.cognition) Array - (Pavolvian conditioning) the elicitation of a conditioned response by stimulation similar but not identical to the original stimulus; Array
is a kind of generalisation, generalization, stimulus generalisation, stimulus generalization

6.  irradiation(n = noun.act) actinotherapy, radiation, radiation therapy, radiotherapy - (medicine) the treatment of disease (especially cancer) by exposure to a radioactive substance; Array
is a kind of therapy
has particulars: phototherapy, curietherapy, radium therapy, x-ray therapy

1.  Act of irradiating, or state of being irradiated; as, irradiation of foods with X-rays can preserve their freshness by killing the bacteria that cause spoilage . [1913 Webster]

2.  Illumination; irradiance; brilliancy. Sir W. Scott. [1913 Webster]

3.  Fig.: Mental light or illumination. Sir M. Hale. [1913 Webster]

4.  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, esp. when a little out of focus. [1913 Webster]

irradiation, n.
1 the process of irradiating.
2 shining, illumination.
3 the apparent extension of the edges of an illuminated object seen against a dark background.

Etymology:
F irradiation or LL irradiatio (as IRRADIATE)

N  light, ray, beam, stream, gleam, streak, pencil, sunbeam, moonbeam, aurora, day, sunshine, light of day, light of heaven, moonlight, starlight, sunlight, daylight, broad daylight, noontide light, noontide, noonday, noonday sun, glow, glimmering, glint, play of light, flood of light, phosphorescence, lambent flame, flush, halo, glory, nimbus, aureola, spark, scintilla, facula, sparkling, emication, scintillation, flash, blaze, coruscation, fulguration, flame, lightning, levin, ignis fatuus, luster, sheen, shimmer, reflexion, reflection, gloss, tinsel, spangle, brightness, brilliancy, splendor, effulgence, refulgence, fulgor, fulgidity, dazzlement, resplendence, transplendency, luminousness, luminosity, lucidity, renitency, nitency, radiance, radiation, irradiation, illumination, actinic rays, actinism, Roentgen-ray, Xray, photography, heliography, photometer, optics, photology, photometry, dioptrics, catoptrics, chiaroscuro, clairobscur, clear obscure, breadth, light and shade, black and white, tonality, reflection, refraction, dispersion, refractivity, shining, luminous, luminiferous, lucid, lucent, luculent, lucific, luciferous, light, lightsome, bright, vivid, splendent, nitid, lustrous, shiny, beamy, scintillant, radiant, lambent, sheen, sheeny, glossy, burnished, glassy, sunny, orient, meridian, noonday, tide, cloudless, clear, unclouded, unobscured, gairish, garish, resplendent, transplendent, refulgent, effulgent, fulgid, fulgent, relucent, splendid, blazing, in a blaze, ablaze, rutilant, meteoric, phosphorescent, aglow, bright as silver, light as day, bright as day, light as noonday, bright as noonday, bright as the sun at noonday, actinic, photogenic, graphic, heliographic, heliophagous, a day for gods to stoop and men to soar, dark with excessive bright.