Simple Definition of hemisphere
: 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
1 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
3 : one of two half spheres formed by a plane through the sphere's center
4 : a map or projection of a celestial or terrestrial hemisphere
Examples of hemisphere in a sentence
a tumor in the right cerebral hemisphere
Did You Know?
Hemisphere includes the prefix hemi-, meaning "half". The northern and southern hemispheres are divided by the equator, the circle halfway between Earth's two poles. The eastern and western hemispheres aren't divided so exactly, since there are no poles in the Earth's east-west dimension. Often the dividing line is said to be the "prime meridian"—the imaginary north-south line that runs through Greenwich, England, from which all longitude is calculated (itself being the 0° meridian). But for simplicity's sake, the eastern hemisphere is often said to include all of Europe, Africa, Australia, and Asia, while the western hemisphere contains North and South America and a great deal of ocean.
Origin and Etymology of hemisphere
Middle English hemispere, from Latin hemisphaerium, from Greek hēmisphairion, from hēmi- + sphairion, diminutive of sphaira sphere
First Known Use: 14th century
HEMISPHERE Defined for Kids
Definition of hemisphere for Students
1 : one of the halves of the earth as divided by the equator or by a meridian
2 : a half of a sphere
3 : either the left or the right half of the cerebrum
hemispheric\ˌhem-ə-ˈsfir-ik, -ˈsfer-\ or
hemispherical\-ˈsfir-i-kəl, -ˈsfer-\ adjective
Seen and Heard
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