What is "v-u-den"

(also romanized Biyuuden, Viyuden, or Biyuden) is a Japanese pop group within Hello! Project. The group was formed in August 2004 and consists of members Rika Ishikawa ( Morning Musume), Erika Miyoshi, and Yui Okada, with Ishikawa being the leader. The name means: , , and . The group officially disbanded on June 29, 2008 after their last concert during their v-u-densetsu 5 tour.

In June 2009, v-u-den was revived as Zoku v-u-den, consisting of Sayumi Michishige, Risako Sugaya and Junjun and released a new song, "ONLY YOU", on a Hello! Project compilation and continued activities until 2011, though Zoku v-u-den briefly appeared during a Hello! Project concert in early 2013 alongside Rika Ishikawa.