Modernism
A broad cultural and artistic movement of the late 19th to mid-20th century that rejected tradition in favor of experimentation, abstraction, and new approaches suited to industrial-age life.
Modernism in art refers to a sweeping shift in how artists conceived their work's purpose and form, beginning roughly in the 1860s (with Manet and the Impressionists) and continuing through the 1960s. Where traditional art sought to represent the world realistically or to narrate history, religion, and mythology, Modernist art turned inward -- toward formal experimentation, abstraction, and the artist's subjective experience.
Modernism was not a single style but a family of related movements: Impressionism, Post-Impressionism, Cubism, Futurism, Expressionism, Dada, Surrealism, Abstract Expressionism, and more. What united them was a break with academic tradition and a conviction that new times demanded new visual language.
In the context of art prints, 'modernist' work typically refers to early-to-mid 20th-century abstraction and figurative experiment -- Matisse's bold color fields, Picasso's Cubist fragmentation, Mondrian's geometric grids, Klee's playful abstraction.