Avant-garde jazz is a form of experimental jazz music that originated in the 1950s and 1960s. It combines elements of traditional jazz with avant-garde and free jazz styles. Some synonyms for avant-garde jazz include experimental jazz, free jazz, improvisational jazz, progressive jazz, and modern jazz. These terms all refer to the unconventional and innovative approach that avant-garde jazz musicians take when creating their music. Avant-garde jazz is often characterized by its use of unconventional harmonies, rhythms, and instrumentation, as well as its emphasis on improvisation and collective creativity. It is a genre that continues to push the boundaries of what is considered jazz, and inspires musicians from a wide range of backgrounds and styles to experiment and explore new ideas.