GOOD DAY (굿데이) was a ten-member South Korean girl group under C9 Entertainment. The group consisted of Heejin, Genie, Cherry, Chaesol, Nayoon, Jiwon, Haeun, Viva, Bomin, and Lucky. The group released their debut mini album All Day Good Day, and the title track Rolly, on August 30, 2017.

They are presumed to be disbanded after C9 Entertainment announced C9GIRLZ (later named Cignature) on November 11, 2019. The group included members Chaesol, Jiwon, Haeun, Viva, and Lucky.

The remaining members Genie, Cherry, Nayoon, and Bomin were revealed as members of Redsquare . Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.