What does "hemisphere" mean?

Hemisphere: Half of the terrestrial globe, or a projection of the same in a map or picture.

Additional senses

  1. 2.The people who inhabit a hemisphere. He died . . . mourned by a hemisphere. J. P. Peters. ten Cerebral hemispheres. (Anat.) See Brain. -- Magdeburg hemispheres (Physics), two hemispherical cups forming, when placed together, a cavity from which the air can be withdrawn by an air pump; -- used to illustrate the pressure of the air. So called because invented by Otto von Guericke at Magdeburg.

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