noun hemi·sphere \ˈhe-mə-ˌsfir\

: a half of the Earth

: half of a sphere : half of a round object

: either of the two halves of the brain

Full Definition of HEMISPHERE

a :  a half of the celestial sphere as divided into two halves by the horizon, the celestial equator, or the ecliptic
b :  half of a spherical or roughly spherical body (as a planet); specifically :  the northern or southern half of the earth as divided by the equator or the eastern or western half as divided by a meridian
c :  the inhabitants of a terrestrial hemisphere
:  one of two half spheres formed by a plane through the sphere's center
:  a map or projection of a celestial or terrestrial hemisphere
hemi·spher·ic \ˌhe-mə-ˈsfir-ik, -ˈsfer-\ or hemi·spher·i·cal \-ˈsfir-i-kəl, -ˈsfer-\ adjective

Examples of HEMISPHERE

  1. a tumor in the right cerebral hemisphere


Middle English hemispere, from Latin hemisphaerium, from Greek hēmisphairion, from hēmi- + sphairion, diminutive of sphaira sphere
First Known Use: 14th century

Other Astronomy Terms

gibbous, nadir, nebulous, penumbra, retrograde, sidereal, syzygy, wane, wax, zenith


noun hemi·sphere \-ˌsfi(ə)r\   (Medical Dictionary)

Medical Definition of HEMISPHERE

:  half of a spherical structure or organ: as a :  cerebral hemisphere b :  either of the two lobes of the cerebellum of which one projects laterally and posteriorly from each side of the vermis
May 25, 2015
callithump Hear it
a noisy boisterous band or parade
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