The genus name Haliaeetus is New Latin for "sea-eagle", from Ancient Greek hali-, "sea-" and aetos, "eagle".
The specific albicilla, "white-tailed", is from New Latin albi-, "white" and cilla, "tail". It measures 66–94 cm (26–37 in) in length with a 1.78–2.45 m (5.8–8.0 ft) wingspan.
White-tailed eagle (Haliaeetus albicilla) are also known as eagle of the rain, sea grey eagle, erne (sometimes ern, ørn), gray eagle, and white-tailed sea-eagle — is a large bird of prey in the family Accipitridae which includes other raptors such as hawks, kites, and harriers.
It is considered a close cousin of the bald eagle and occupies the same ecological niche, but in Eurasia.
Small disjunct resident populations occur in southwesternmost Greenland and western Iceland.
The former has been proposed as a distinct subspecies, groenlandicus, based on their very large size and body proportions.
All bare parts are yellow in color, including both the bill and the legs.
In juvenile birds, tail and bill are darker, the tail becoming white with a dark terminal band in sub-adults.
This species has broad "barn door" wings, a large head and a large thick beak.
The adult is mainly grayish-brown except for the slightly paler head and neck, blackish flight feathers, and distinctive white tail.