Definition of hemisphere
1a : a half of the celestial sphere as divided into two halves by the horizon (see horizon 1b), the celestial equator, or the eclipticb : half of a spherical or roughly spherical body (such as a planet); specifically : the northern or southern half of the earth as divided by the equator (see equator 2) or the eastern or western half as divided by a meridian (see meridian 4a(2)) affected by the weather in the other hemispherec : the inhabitants of a hemisphere of the Earth
5 : cerebral hemisphere an injury to the left 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 English Language Learners
Definition of hemisphere for English Language Learners
: a half of the Earth
: half of a sphere : half of a round object
: either of the two halves of the brain
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
What made you want to look up hemisphere? Please tell us where you read or heard it (including the quote, if possible).