This is fundamentally the Male equivalent of a "Girl's Night," except that instead of watching Sex and the City DVDs, swooning over Orlando Bloom, and eating Haagen Daaz; A Square Table Meeting is typically comprised of watching a classic 80s-90s Action movie (such as Die Hard) and/or an MMA or boxing event, eating some form of grilled meat or fried cheese product, and having a tournament of some kind. Hold em Poker is most common, Beer Pong and Beirut are also typical; as are impromptu Burping and Farting contests.
The Square Table Meeting has its origins in the popular series of Miller Lite commercials where a quorum of men's men concoct, (and an ancient man known only as "The Scribe" records,) decrees governing manly behavior, which are appropriately dubbed, "Man Laws."
Some of the more famous Men of the Square Table include Jerome Bettis, formerly of the Pittsburg Steelers, actors Burt Reynolds and Eddie Griffin, wrestler Triple H, and that dude who cut off his own arm when it was trapped under a boulder.
"Hell yeah, we're having a Square Table Meeting at RJ's! Grill goes hot at 6, we're watching Predator at 7:30, UFC event starts at 10."