Hen harrier (Circus cyaneus)

The hen harrier (Circus cyaneus) is a bird of prey in the family Accipitridae. 
The bird breeds in Eurasia, winters in southern Europe and southern temperate Asia.

Traits:
- White patch on rump;
- Five finger tips (five prominent primaries on the wings);

accipitrinus Latin accipitrinus hawk-like (accipiter: hawk).
In both Latin and Greek, the root of the word "circus" means "ring" or "circle". The Latin word circus comes directly from the Greek word κίρκος (kírkos), which also means "circle" or "ring". This etymology describes the shape of the ancient Roman arenas and the modern performance spaces where circuses are held. 
The term "cyaneus" is a Latin word meaning "dark blue" or "sea blue". It is derived from the Ancient Greek word kuáneos (κυάνεος), which also refers to a dark blue color, sea blue, and was used to describe dark blue enamel or lapis lazuli. 
The term "hen harrier" refers to its former habit of preying on free-ranging fowl.