New Skylake MacBook Pros coming October 27.
MacBook 'Brick' Codename Speculation
The name originates from 9to5Mac, apparently based on the same Asian sources as the "rainbow" iPod Nanos. The "rainbow" iPod nano rumors were apparently misinterpreted as multi-colored individual iPods, but in retrospect, it seems the term instead related to the colors of the rainbow that the new iPod nano are now available in.
Since then, the site has been told that the new MacBook update will be 'all about the Brick'. The exact meaning of which is left up for debate.
Some are speculating that it is a completely separate device, but based on 9to5's reports it seems clear it has to do specifically with the MacBook which is also rumored to have a glass touchpad.