Britannia

[bri-tan-ee-uh, -tan-yuh] /brɪˈtæn i ə, -ˈtæn yə/
noun
1.
the ancient Roman name of the island of Great Britain, especially the S part where the early Roman provinces were.
2.
the British Empire.
3.
Chiefly Literary.
  1. Great Britain.
  2. the United Kingdom of Great Britain and Ireland.
4.
the figure of a seated woman with trident and helmet used as a symbolic representation of Great Britain and the British Empire.
British Dictionary definitions for Britannia

Britannia

/brɪˈtænɪə/
noun
1.
a female warrior carrying a trident and wearing a helmet, personifying Great Britain or the British Empire
2.
(in the ancient Roman Empire) the S part of Great Britain
3.
short for Britannia coin