Act or process of making a shade. [1913 Webster]
That filling up which represents the effect of more or less darkness, expressing rotundity, projection, etc., in a picture or a drawing. [1913 Webster]

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OXFORD DICTIONARY

shading, n.
1 the representation of light and shade, e.g. by pencilled lines, on a map or drawing.
2 the graduation of tones from light to dark to create a sense of depth.

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THESAURUS

shading

arrangement, atmosphere, balance, black spot, blackening, blocking the light, bloom, blooping, brushwork, clouding, color, composition, covering, curtaining, darkening, definition, denigration, design, dimming, draftsmanship, eclipsing, extinguishment, flare, fringe area, ghost, gradation, grading, graduation, granulation, grid, grouping, hard shadow, image, interlaced scanning, line, melanization, mixing, monitoring, multiple image, nigrification, noise, obfuscation, obnubilation, obscuration, obscurement, obumbration, occulting, overcast, overclouding, overshading, overshadowing, overshadowment, painterliness, perspective, picture, picture noise, picture shifts, rain, rolling, scanning, scanning pattern, scintillation, screening, shadow, shadowing, smirch, smirching, smudge, smudging, smut, smutch, smutching, snow, snowstorm, switching, technique, telecasting, televising, tone, treatment, values, veiling

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ROGET THESAURUS

shading

Darkness

N darkness, absence of light, blackness, obscurity, gloom, murk, dusk, Cimmerian darkness, Stygian darkness, Egyptian darkness, night, midnight, dead of night, witching hour of night, witching time of night, blind man's holiday, darkness visible, darkness that can be felt, palpable obscure, Erebus, the jaws of darkness, sablevested night, shade, shadow, umbra, penumbra, sciagraphy, obscuration, occultation, adumbration, obumbration, obtenebration, offuscation, caligation, extinction, eclipse, total eclipse, gathering of the clouds, shading, distribution of shade, chiaroscuro, noctivagation, black body, hohlraum, black hole, dark star, dark matter, cold dark matter, dark, darksome, darkling, obscure, tenebrious, sombrous, pitch dark, pitchy, pitch black, caliginous, black, sunless, lightless &c (sun) (light), somber, dusky, unilluminated &c (illuminate), nocturnal, dingy, lurid, gloomy, murky, murksome, shady, umbrageous, overcast, cloudy, darkened, dark as pitch, dark as a pit, dark as Erebus, benighted, noctivagant, noctivagous, in the dark, in the shade, brief as the lightning in the collied night, eldest Night and Chaos, ancestors of Nature, the blackness of the noonday night, the prayer of Ajax was for light.

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