Term: Painterly

Karl Schmidt-Rottluff, "Self-Portrait"

The term painterly is used to describe a painting done in a style that embraces, shows, and celebrates the medium it's created in (be it oil paint, acrylics, pastels, watercolor, etc.), rather than tries to hide the act of creation.

In centuries past (and in various modern art movements such as Photorealism) painters worked hard to eliminate or conceal any evident brushmarks or texture in a painting, blending and smoothing to hide all evidence of how the painting was created.

It doesn't mean the paint has to be thick or impasto, it can be thin. The style or approach just doesn't try to hide the fact that a brush or knife were used to create the artwork, it uses this to create an image that could only be done with paint (or art materials).

According to the Tate Gallery's Glossary the term painterly "carries the implication that the artist is reveling in the manipulation of the oil paint itself and making the fullest use of its sensuous properties."

From About.com