¦ noun
1. a half of a sphere.
2. a half of the earth, usually as divided into northern and southern halves by the equator, or into western and eastern halves by an imaginary line passing through the poles.
a half of the celestial sphere.
3. (also cerebral hemisphere) each of the two parts of the cerebrum (left and right) in the brain of a vertebrate.
Derivatives
hemispheric adjective
hemispherical adjective
hemispherically adverb
Origin
ME: from OFr. emisphere, via L. from Gk hemisphairion, from hemi- 'half' + sphaira 'sphere'.