implied line - lines that dim, fade, stop or dissappear. The missing portions are visually completed by the viewer.
curvilinear - the use of curved lines. (fingerprints are a great example)
perspective - creating the illusion of a 3-D image on a 2-D surface.
achromatic value - relating to differences of light and dark, disregarding color.
cast shadow - the dark area that occurs on a surface as a result of something being placed between that surface and a light source.
chiaroscuro - 1) distribution of light and dark. 2) an art technique that blends light and shade gradually to create a 3-D illusion.
highlight - the portion of an object that appears to receive the greatest amount of direct light.
shadow, shade, or shading - the darker values on the surface of an object that appear to receive the least amount of direct light.
tenebrism - a painting technique that exaggerates or emphasizes the effects of chiaroscuro.
representational art - type of art that uses the art elements to create an image that looks like an actual object.