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.
The Impressionists, Fauvists and the Abstract Expressionists tended strongly to be painterly movements.