The term 'Retro ART STYLE' can be summarized as a combination of the crossword solutions DECO (4 letters) and ART STYLE. DECO is short for ART Deco, a popular ART movement that originated in France in the early 20th century. It was characterized by geometric shapes, bold colors, and ornamental designs. ART STYLE refers to the various artistic styles that have been developed over time, such as Impressionism, Expressionism, Cubism, and Surrealism. Retro ART STYLE is a combination of these two elements, creating a unique aesthetic that is both modern and nostalgic.