c. 1600, "representation of light and shade in a drawing;" 1610s, "act or process of making shade or as shade," verbal noun from shade (v.).
Entries linking to shading
shade v.
c. 1400, shaden, "to screen from the sun or its heat," from shade (n.). From 1520s as "to cast a shadow over;" the figurative use in this sense is from 1580s. The meaning in painting and drawing is from 1797. In reference to colors, 1819. Related: Shaded; shading.