MAMAMOO (Hangul: 마마무) is a four-member South Korean girl group under RBW. The group consists of Solar (솔라), Moon Byul (문별), Whee In (휘인), and Hwa Sa (화사). They are recognized for their retro, jazz, R&B concepts and their strong vocal performances.

The group made their official debut on June 18 with lead single "Mr. Ambiguous" from their first extended play Hello. The music video for "Mr. Ambiguous" contained cameo appearances from many well-known K-pop industry figures such as CNBLUE''s Jonghyun, Baek Ji-young, Wheesung, Jung Joon-young, Bumkey, K.Will, and Rhymer of Brand New Music. The album contained three previously released collaborations and four new songs. The group made their first live appearance on the June 19th episode of M! Countdown.

On November 21, Mamamoo released their second extended play Piano Man with the title track "Piano Man". The title song peaked at No41 on Gaon''s Digital chart. By the end of 2014, Mamamoo ranked 10th highest among idol girl groups for digital sales, 19th in album sales, and 11th in overall sales according to Gaon''s year-end rankings. On the January 10th episode of competitive singing show Immortal Songs 2, Mamamoo performed a rendition of Joo Hyun-mi''s "Wait a Minute", reaching the final round before losing to Kim Kyung-ho.