This term derives from the “grain” of wood, which makes sense because it means simulating wood grain through advanced painting methods. Sloppy graining technique can look horrible, but in the hands of an expert, graining can make silk from a sow’s ear. (Sorry. It’s the Southerner in us coming out.) It can be applied to both interior and exterior surfaces and used on either actual wood or another base material, such as metal.
An artisan who has taken the care to analyze various wood structure and patterning can create amazing simulations of anything from basics like cherry, mahogany, walnut, and oak to exotics like burl, rosewood, macassar, wenge, satinwood, and ebony. Of course, a craftsman needs just the right tools in order to transform the bland into the stunning. Specialty brushes and combs pulled through translucent glazes over base coats of colors and stains create a basic graining, but more detailed imitations of highly figured wood require very detailed drawing into the glaze.
See also: faux bois