Technically, break means to split into pieces, and so forth. The reason it is spoken of as a 'coffee break', I think, is because that time slot breaks the work morning in half (or into any sort of segment.) It does not, however, imply a pause or stop.
This is where the 'actual' title of CB comes to play - or, at least, the one registered and kept for a while in Japan, Chrono Brake. That does indeed mean to slow down, often with the intent of stopping. It seems the use of both of these for CB has caused some confusion, but brake and break really do not mean the same thing.
