Brick

A brick is when a device no longer functions.

What is a brick

 * A console that can't turn on without additional hardware (for example, a 3DS might need an ntrboot cartridge to fix corrupted firmware partitions or a NAND header)

What isn't a brick

 * A console that needs support files to turn on (for example, a 3DS might need  on the SD card that boot9strap can find)