Painterliness is a concept based on the German term malerisch (painterly), a word popularized by Swiss art historian Heinrich Wölfflin (1864-1945) to help focus, enrich and standardize the terms being used by art historians of his time to characterize works of art. It is the opposite of linear, plastic or formal linear design.
An oil painting is painterly when there are visible brushstrokes, the result of applying paint in a less than completely controlled manner, generally without closely following carefully drawn lines. Works characterized as either painterly or linear can be produced with any painting media: oils, acrylics, watercolors, gouache, etc. Some artists whose work could be characterized as painterly are Pierre Bonnard, Francis Bacon, Vincent van Gogh, Rembrandt, Renoir, and John Singer Sargent. In watercolor it might be represented by the early watercolors of Andrew Wyeth.
In contrast, linear could describe the painting of artists such as Botticelli, Michelangelo, and Ingres, whose works depend on creating the illusion of a degree of three-dimensionality by means of "modeling the form" through skillful drawing, shading, and an academic rather than impulsive use of color. Contour and pattern are more in the province of the linear artists, while dynamism is the most common trait of painterly works.
Painterly art often makes use of the many visual effects produced by paint on canvas such as chromatic progression, warm and cool tones, complementary and contrasting colors, broken tones, broad brushstrokes, sketchiness, and impasto.
Although painterly generally refers to a certain use of paint in art, it happens that some forms of sculpture make use of apparently random surface effects which, if not exactly resembling brushstrokes, contain the traits of painterliness. The application of the term painterly outside of painting may help the viewer or listener experience more deeply the significance of Auguste Rodin's surfaces or Richard Strauss's flow of chromatic harmonies.
"Painterly" is used to describe computer software, especially mobile apps, designed to create special effects on photographs, mimicking recognizably artistic styles such as oils, watercolors, Japanese woodcuts, etc., or based on styles like van Gogh or Monet, and so on. The resulting photographs are also called "painterly".