Blazer is a term commonly used at the bar scene at The University of Iowa. It is used to insult someone that looks like or is acting like a total fogie. Someone who loves public transportation, WWII, wearing two-piece track jumpsuits and Hawaiian shirts, and falling asleep watching baseball games is a Blazer. Think of Clint Eastwood in Gran Torino, but just the cranky old part of him, not the totally badass part.
The kid on any type of online game that doesn't get any kills or dies more times than he gets kills (terrible kill to death ratio) because of 'the lag'. There is usually no lag and the person playing is usually a lier to make him sound better at the game.