Hemisphere

Hemisphere means half (hemi) of the Earth or any other  sphere.
The Northern Hemisphere means everything north of the Equator, which includes, North America, Central America, the northern part of South America, Europe, Asia, northern Africa, and the Middle East.
The Southern Hemisphere means everything south of the Equator, which includes most of South America, most of Africa, Australia, and Antarctica.
The Western Hemisphere includes North America and South America, and has the Pacific Ocean on its western border and the Atlantic Ocean on its eastern border.
The Eastern Hemisphere includes Europe, Asia, and Africa, and has the Atlantic Ocean on its western border and the Pacific Ocean on its eastern border.
It can also mean the land hemisphere or the water hemisphere.