Jamcomming also known as DDOSing is when someone intentionally hacks the router of another person to the point of it not constantly disconnecting, with the intent of either settling personal disputes with them or stealing data from them they deem valuable. Jamcomming is normal in high-crime, high-poverty communities where Wi-Fi speeds are so low that jam coms are mistaken for a normal disconnection.
Jamcomming can also happen on a larger scale and if hackers CAN, they WILL jamcom the servers of larger sites like Reddit, Facebook, or Tumblr. With the intent of exposing flaws in development or to stop the spread of a political ideology they disagree with that is growing on said site.
Jamcomming comes from the Watchdogs series, where a tool called a "Jam Com" can be used with DDOS-like features like preventing calls, preventing police scans, preventing hacks, among other things.
Person 1: Why does the Wi-Fi always disconnect?
Person 2: Jamcomming, that's why!