In modern electronic dance music, House, Garage, Trance etc., the breakdown is the opposite. It's the part of the tune where the driving bass and kick drum parts are dropped out of the mix for a few loops.
It's mainly a device to add variation to what is fundamentally a highly repetitive group of genres- and it allows the producer to give the tune a big lift when the beat comes back in.
At least in this genre the word breakdown is used in its most literal sense of breaking the arrangement down. I've never previously understood how the word comes to describe the faster and more elaborate section on bluegrass and old-time styles.
Thanks for the education.
Cheers
Dave