Wiktionary
n. Japanese pop music influenced by western genres
Wikipedia
J-pop (often stylized as J-POP; jeipoppu; an abbreviation for Japanese pop), natively also known simply as pops, is a musical genre that entered the musical mainstream of Japan in the 1990s. Modern J-pop has its roots in traditional Japanese music, but significantly in 1960s pop and rock music, such as The Beatles and The Beach Boys, which led to Japanese rock bands such as Happy End fusing rock with Japanese music in the early 1970s. J-pop was further defined by new wave groups in the late 1970s, particularly electronic synthpop band Yellow Magic Orchestra and pop rock band Southern All Stars.
Eventually, J-pop replaced kayōkyoku ("Lyric Singing Music", a term for Japanese pop music from the 1920s to the 1980s) in the Japanese music scene. The term was coined by the Japanese media to distinguish Japanese music from foreign music, and now refers to most Japanese popular music. The musical genre has been immensely influential in many other music styles, and hence those of neighboring regions, where the style has been copied by neighboring Asian regions, who have also borrowed the name to form their own musical identities.