Just to confirm that Juggerling is being serious. It is called a chaser when ordered with a pint and is drunk after the pint. Quite simple. A normal shot of whisky.
Alternatively if you drink the whisky first and then the beer, that's usually called a boilermaker - can also be mixed together and or the shot glass dropped into the pint at which point some people will still call it a boilermaker, others a depth charge.