Myasthenia gravis. Myasthenia gravis (MG) is an autoimmune disease that weakens the muscles. The name comes from Greek and Latin words meaning grave muscle weakness. But most cases of MG are not as grave as the name implies. In fact, most people with MG can expect to live normal lives.
To be more precise, it is when a player records double-digit values for three statistical categories. A basketball player accomplishes a triple double by reaching double digits in 3 of the following: assists, rebounds, points, steals, and blocks. In most cases the 3 doubles are assists, rebounds, and points. There have also been 4 quadruple doubles in the NBA, when players reached double digits in 4 of the above stats.
1 He had 18 points, 22 rebounds and 13 assists.  Averaging a triple-double in a single season: Oscar Robertson is the only player in NBA history to achieve this feat. During the 1961â62 season, Robertson averaged 30.8 points, 12.5 rebounds, and 11.4 assists per game.