- any of several large brown gull-like predatory birds of the genus Catharacta, related to jaegers, especially C. skua(great skua ), of colder waters of both northern and southern seas.
- jaeger (def. 1).
- any predatory gull-like bird of the family Stercorariidae, such as the great skua or bonxie (Stercorarius skua) or arctic skua (S. parasiticus) both of which harass terns or gulls into dropping or disgorging fish they have caught