DICT.TW Dictionary Taiwan

 scum·ble /ˈskʌmbəl/
 (vt.)將色彩弄淡,漸使顏色淺淡漸淡,漸淡畫法,薄塗

 Scum·ble v. t. [imp. & p. p. Scumbled p. pr. & vb. n. Scumbling ]  Fine Arts To cover lighty, as a painting, or a drawing, with a thin wash of opaque color, or with color-crayon dust rubbed on with the stump, or to make any similar additions to the work, so as to produce a softened effect.
 ◄ ►

 scumble
      n : the application of very thin coat of color over the surface
          of a picture