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 23, 2015
debouch Hear it
to emerge or cause to emerge
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