MXM (also known as MXM (BRANDNEWBOYS)) is the first subunit of the boy group AB6IX (formerly called BRANDNEWBOYS) under Brand New Music. They officially debuted on September 6, 2017 with their first mini album Unmix.
Following Lim Young Min's departure from AB6IX on June 8, 2020, it is safe to assume that the unit disbanded despite still being listed on the Brand New Music's artist's page.[1]
MXM stands for "MIX & MATCH" and "MORE X MORE", meaning that it will show a new charm by combining the charms of the two different things, and that it will continue to grow further.[2]