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]
Illumination; irradiance; brilliancy. Sir W. Scott. [1913 Webster]
Fig.: Mental light or illumination. Sir M. Hale. [1913 Webster]
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]

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OXFORD DICTIONARY

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)

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THESAURUS

irradiation

X-ray dosimetry, X-ray therapy, anhydration, arc lighting, black and white, blast-freezing, bottling, brining, canning, chiaroscuro, cobalt therapy, contrast, corning, curietherapy, curing, decorative lighting, dehydration, desiccation, direct lighting, dry-curing, drying, electric lighting, emanation, embalming, enlightenment, evaporation, festoon lighting, floodlighting, fluorescent lighting, freeze-drying, freezing, fuming, gaslighting, glow lighting, highlight, highlights, illumination, incandescent lighting, indirect lighting, interstitial irradiation therapy, irradiance, irradiancy, irradiation therapy, isotope therapy, jerking, light, light and shade, light source, lighting, luminous energy, marination, mummification, overhead lighting, photosensitivity, pickling, potting, quick-freezing, radiance, radiancy, radiant energy, radiation, radiation therapy, radiotherapeutics, radiotherapy, radium therapy, radiumization, ray therapy, refrigeration, roentgen ray therapy, roentgenization, roentgenometry, roentgenotherapy, roentgentherapy, salting, seasoning, sidelight, smoking, spot lighting, stage lighting, strip lighting, stuffing, taxidermy, tinning, tonality, visible radiation

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ROGET THESAURUS

irradiation

Light

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.

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