Adverb
en plein (not comparable)
(gambling) Being a simple bet on a single specific outcome, especially a number in roulette.
American impressionists too, such as those of the Old Lyme school, were avid painters en plein air. Source: Internet
Boudin taught Monet " en plein air " (outdoor) techniques for painting. Source: Internet
Landscape art is ubiquitous in Vermont, from crisp blackand-white photographs of wheezing barns to en plein air tributes to the seasons — “distillations of the way people want to see Vermont,” suggested Costantino during a recent gallery visit. Source: Internet
Painting "en plein air” (AKA outside) allowed impressionist painters to capture the transient nature of sunlight, which became a huge focus for painters who adopted the style. Source: Internet
In Canada, the Group of Seven and Tom Thomson are examples of en plein air advocates. Source: Internet
The Newlyn School in England is considered another major proponent of the technique in the latter 19th century. citation The popularity of painting en plein air increased in the 1840s with the introduction of paints in tubes (like for toothpaste ). Source: Internet