What is "metriacanthosauridae"

Metriacanthosauridae is an extinct family of carnivorous allosauroid theropod dinosaurs. They tended to be large predators, some growing to sizes of . Metriacanthosaurids are carnosaurs, and many were initially classified within Megalosauridae or Allosauridae. A gigantic tooth belonging to what most likely is a giant sinraptorid has been described by Xu and Clarke in 2008.