To what does the name of the musical genre which Stan Kenton produces in refer to?
Stan Kenton:  Though Kenton was to have several pop hits from the early 1940s into the 1960s, much like earlier band leader Paul Whiteman, he categorized his music as forward looking. Stan Kenton:  In Kenton's own words, it was "Progressive jazz". Progressive music:  The word "progressive" comes from the basic concept of "progress", which refers to development and growth by accumulation, and is often deployed in numerous music genres such as progressive country, progressive folk, progressive jazz, and (most significantly) progressive rock.
development and growth by accumulation