A hemisphere is one half of the earth. 半球
noun [具体名词] （地球的）半球；脑半球；（球体的）一半 the northern / southern / eastern / western hemisphere
Of course, were they the first people in the Western hemisphere? 当然，他们是西半球的第一批人吗？
hemi-
hemisphere
半球（hemi+sphere 球）
hemi(半) + spher(球) + e → 半球
