Hacker Geek Speak for Radio Spectrum, the frequencies assigned for all radio traffic. Includes CB, Cell Phones, Wireless, Aeronautic and Nautical, etc. Extends from 3MHz to 300Ghz. Large part of this spectrum is assigned for US Government use only. Upper end also includes Scientific Research and Non-Terrestrial Crafts and Experimentation.
Not sure where that traffic I'm scanning falls in the RadSpec, but around 800MHz, so probably cell phone chatter.